Chemistry 216 Course Pack Synthesis and Characterization of Organic Compounds 9781533960955

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Chemistry 216 Course Pack Synthesis and Gumball Watteison

Characterization of Organic

Compounds

Department of Chemistry

John P. Wolfe, Ph.D.

University of Michigan

Ginger Shultz, Ph.D.

2023-2024

macmillan learning curriculum solutions

Table of Contents

Course Pack Instructions Course Learning Goals Calculations Guide .. .. . ..

Copyright

2023 by John P. Wolfe and Ginger Shultz

Photos provided by Hayden-McNeil, LLC

5-6 7-9

Recrystallization Guide

11-12

Thin Layer Chromatography Guide ................. Separations Guide

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Permission in writing must be obtained from the publisher before any part of this work may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying and recording, by any information storage or retrieval system.

Printed in the United States of America 10987654321

ISBN 978-1-5339-6095-5

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status

17-19

Spectroscopy Quick Reference Guides

21

Infrared Spectroscopy Table

23-24

NMR Spectroscopy Table

25

Practice Problems for Quizzes All rights reserved.

13-16

•*.*..*.............................. .......0

27-74

Course Pack Instructions CHEM 216 builds on the experimental approach started in CHEM 211. In this course you will

use microscale equipment, which will require you to develop manual dexterity and You will evaluate the results of your experiments by

care in working in the laboratory.

checking for product identity and purity using various analytical methods, including IR and NMR spectroscopy, TLC, and melting point. You will be expected to keep laboratory notebook, and to complete worksheets where you analyze results or answer other questions related to the experiment. For some experiments you will work in small groups, and for

each

group project, your group will formulate hypotheses that you will test using

experiments that you design and implement with faculty and GSI guidance.

02 1

The front pages of this course pack are intended to provide you with resources that will

help you prepare for, conduct, and analyze the results of your experiments. These include

a description of the learning goals for the course, guidelines for maintaining : lab notebook, crafting a hypothesis, and carrying out calculations you will need to conduct experiments. There are also guides provided on some of the common experimental techniques such as TLC and recrystallization.

Although the majority of this course is focused on laboratory experiments, you will be

introduced to some reactions you have not (and will not) encounter in the Chem 210 and Chem 215 lecture courses. In addition, you will also learn to analyze and interpret IR and

NMR spectra. The majority of the

pages in this course pack consist of problems, taken

directly from quizzes given in past semesters, that spectroscopy problems and other course related topics.

will

help you practice solving

The answer key for this coursepack is not contained within these pages, but instead posted as file on Canvas. We advise you use the answer key appropriately, and with

caution

make to create

the presence of an

too easy for

one

answer key can be an

impediment to learning; answer keys

to confuse the ability to understand an answer with the ability

answer/solve a problem. Be aware that some problems may have more than

one possible answer that is consistent with data presented. Our recommendation that you do not save all problems for the few days prior to the quiz, but rather work on the

problems as the topics come up throughout the course of the semester.

Course Learning Goals The primary goal of the course is to build on concepts of structure and reactivity from

Chemistry 210 and 215, as

you

learn to predict the behavior of compounds that they

use in lab. The experiments in Chemistry 216 are problem-based and are designed to engage you with authentic but accessible problems, which practicing organic chemists routinely encounter in lab. This is based on a learning model that says that meaningful learning occurs when we make mistakes doing difficult tasks rather than

when we are repeatedly successful :

easy ones. The learning objectives are aimed at

building competency in laboratory technique and developing scientific process skills, while simultaneously reinforcing concepts around structure and reactivity. The specific learning goals

of the course are described below. Use them to assess your

progress through out the

term.

LABORATORY TECHNIQUES Lear1

Goals

1. Thin Layer Chromatography a. Understand the purpose and applications of TLC b. Explain how TLC (or chromatography) works Select ppropriate solvents & adjust solvent ratio to optimize resolution and position of spots

d. Interpret TLC to differentiate between starting materials, products, and e.

impurities Use TLC to monitor a reaction or column

f. Use TLC in combination with other information to identify an unknown 2.

compound Recrystallization

a. Understand the purpose of recrystallization

b. Explain how recrystallization works d. e.

3.

Select appropriate solvents for single and mixed solvent recrystallization Successfully purify reaction products using recrystallization Recover crude product from mother liquid if recrystallization fails

Calculations d.

b. C.

Understand what crude yield, % yield, and theoretical yield are, how they

differ, and what information is gleaned from each Calculate crude yield, % yield, theoretical yield

Explain concentration, how it differs from "amount", and why it is important

to know d.

Explain what a molar equivalent is and how it is used Convert between moles, molarity, density, and molar equivalents

SPECTROSCOPY Learning Goals a. Explain what spectroscopy is, differentiate between IR and NMR, the type b.

of information provided by each, and their limitations Use: spectral database to obtain

IR, NMR, and m.p. data

Calculations Guide For each experiment you will need to do some calculations in your lab notebook before

you get to and

1.

Infrared Spectroscopy

Identify the main components of an Infrared spectrum (units, regions, peak

characteristics)

Identify major functional groups and bonds in the functional group region

using a table

c. Interpret authentic spectra collected in lab and identify if it corresponds to product, starting material,

lab. To

get started you should read over the procedure (posted on CTools)

identify quantities of reagents that aren't useful to you in their present form. For

instance, in the example procedure shown below you are asked to dissolve 0.01 mol of N-allylaniline in dichloromethane to give a molar solution. You can't measure

moles or molarity

that you know how

directly so you'll need to convert to either grams or milliliters so ch of each reagent to measure out. See the example calculations

below as model for how to determine the quantity to measure in lab starting from

moles, molar equivalents or molarity.

or reaction/recrystallization solvent

d. Compare spectra obtained in lab to spectral data from the literature e. Match a set of compounds the appropriate IR spectrum f.

Use an IR spectrum along with other characterization methods to identify unknown compounds Use

an

IR spectrum, with and without other information, to predict a

molecular structure 2.

NMR Spectroscopy a.

Interpret features of a spectrum including: 1) number of peaks; 2) peak position; 3) integration; and 4) splitting, to determine fragments or the

complete structure of a compound b. Do reverse interpretation starting from

structure predict number of

CH2Cl2 1.0 equiv

1.2 equiv

N-alllylaniline

allylisocyanate

N..-Diallyl-N1-Phenylurea

MW = 133.19

MW = 83.09

MW = 216.13

Example Procedure (brief): Dissolve 0.01 mol of N-allylaniline in dicholoromethane to give a 1 molar solution. Add 1.2 molar equivalents of allylisocyanate and stir at rt for 1 h. Evaporate solvent and recrystallize product.

peaks, peak position, integration and splitting in a spectrum. C.

Interpret coupling constants and use them to differentiate between

d.

Interpret both 'H and 13C NMR and be able to differentiate between the type

This procedure afforded 1.6 g of the product.

structural isomers

e.

f.

of information that can be obtained by each Match a set of compounds to the appropriate NMR spectrum Use an NMR spectrum, with and without other information, to predict a

Converting Moles to Grams:

molecular structure

determine, such as mass or volume. To convert moles to grams we multiply fractions using the molecular weight of the component of interest. Molecular weights are typically given in amu (atomic mass units), but these values are

Use an authentic NMR spectrum, along with IR, m.p., and TLC, to identify an unknown compound

Compare an authentic NMR spectrum obtained in lab to spectral data from

We

cannot (easily) directly measure moles. So,

that we can easily

we need to convert that unit to one

the same as grams/mol. So,

the literature

1 mole of N-allylaniline = 133.19 g To calculate grams of a reactant starting from moles we do the following:

Moles of reactant x molecular weight of reactant (grams / mol) = grams of reactant Applied to our example procedure,

we need to determine

starting from moles (0.01 mol). We do the following:

grams of N-allylaniline

0.01 mol x 133.19g/1mol = 1.3319 g (which can

weigh with some accuracy.

we can round up to

1.33 g - a value we

We can

calculate the amount of allylisocyanate needed (0.012 mol) manner; 0.012 mol x 83.09g/1mol = 0.9971 g (which we can round up to can weigh with some accuracy).

After each experiment you will need to calculate the yield of product that you obtained

help us relate the moles

of one

reagent to the moles of another.

the moles of N-allylaniline. To do this we multiply the moles of one reagent times the molar equivalents of the other;

Moles of first reagent x molar equivalents of second reagent = moles of second reagent Applied to our example procedure, we need 1.2 molar equivalents of allylisocyanate N-allylaniline). Because we start with 0.01

mol

of N-allylaniline we

determine the amount of allylisocyanate by multiplying 0.01 X 1.2 0.01 mol x 1.2 = 0.012 mol So,

Calculating Percent Yield

1.00 - a value we

on

to

M solution we

same as

in a similar

From our example procedure we need to calculate the moles of allylisocyanate based

(relative

dissolve 0.01 mol of N-allylaniline in dichloromethane to give a

need to dissolve 1.33g of N-allylaniline in 0.01 liter of dichloromethane (which is the

Molar Equivalents: Molar equivalents

So

e cd

as a

measure of how efficient the reaction was. Typically this is given as a

percent

yield. Before you calculate percent yield you need to know the theoretical yield.

Theoretical yield is the maximum amount of product that can possibly be formed in a reaction. This is equal to the amount (in moles) of the limiting starting reagent (the one present in the lowest molar amount. So in this case, the theoretical yield of the urea product is 0.1 mol (the same as the N-allylaniline, which is the limiting reagent). To calculate theoretical yield we need to convert moles to grams again: 0.01 mol x 216.13 g/mol = 2.1613 g (which we will round to 2.16). Out theoretical yield in this case is 2.16g of product. Once you have theoretical yield you

can

use that along with the actual yield to

determine the percent yield. For percent yield of the reaction we divide amount

obtained by theoretical amount possible and multiply by 100. So, if we obtain 1.6 g of product:

we need to use 0.012 mol of allylisocyanate.

% yield = (1.6g/2.16g) x 100 = 74%

Molarity to give mL of solvent in a solution:

Calculating Percent Yield of an Unknown Compound

To calculate the mL of dichloromethane needed to prepare a allylaniline in dichloromethane you need to do the following:

molar solution of N-

The

So, a 1 molar (M) solution of N-allylaniline would contain

To dissolve

mole of N-allylaniline per

need to convert grams to moles.

0.01 mol of N-allylaniline in dichloromethane to give

M solution we

use the following information. M

mole/liter; and 0.01 mol of N-allylaniline = 1.33 g (we calculated this above)

We then solve the following equation: 0.01 mol/X liters

1

mol/1 liter

unknown starting material to prepare

an

is to first try to assign the structure of the product and then use the molecular weight

molarity of a solution is defined as moles of material dissolved in 1 liter of solvent.

liter of solvent. To calculate how to form a solution

For some experiments you will use an

unknown compound and will be asked to identify (assign a structure to) this unknown product. The best way to calculate percent yield for your unknown product

Calculating Molarity (when preparing solutions):

The answer is 0.01 liter

of that structure to calculate the percent yield as above.

Recrystallization Guide Recrystallization is a technique that is used to purify compounds. The first identify a suitable recrystallization solvent

step is

to

by determining the solubility of your

compound in the solvents that are available in the lab. This can be done empirically, but you can save yourself some time and effort by predicting which solvents your compound will or will not be soluble in. Start with the general rule of thumb "like

dissolves like" Generally speaking, polar solvents (i.e. water) dissolve polar or ionic

compounds, and nonpolar solvents dissolve nonpolar compounds. There are a few details that you should keep in mind. Halogenated solvents (i.e. dichloromethane) are relatively nonpolar as compared to oxygen containing solvents like diethyl ether.

Solubility also depends on how many hydrocarbon groups (-CH2-) are present in the

compound you are trying to dissolve. Compounds with less than 4 carbon atoms and an O or N atom tend to be water soluble.

water soluble

NOT water soluble

Once you've used your chemical knowledge to select a few solvents to try, you can the solubility of your compound. To test the solubility of compounds that are liquid at room temperature add about 0.1 ml of the liquid to about mL of solvent. If it dissolves it is soluble. For compounds that are solid at room temperature you can add 40 mg of the compound to 1 mL of solvent and then stir the mixture for minute or two to see if the

naterial dissolves Keep in mind that solubility is a relative term, and

that a compound can be partially soluble in a solvent. In fact, partial solubility is what are looking for, as solvents in which your compound is partially soluble are ideal for recrystallization. Case C: compound i not soluble at low dissolves with increasing temperature

high

Case A: compound is soluble in this solvent at all temperatures

solubility

Casel

low

compound is not soluble

any

solubility high

temperature

emperature

Temperature has an influence on solubility. Therefore when identifying a solvent for recrystallization you should test the solubility of your compound in the solvent of interest as heat is applied. The ideal solvent for recrystallization is one that will

dissolve your compound only when the temperature is increased (see Case C above). When no single solvent is ideal for recrystallization of a compound, a mixed solvent 11

10

recrystallization can be performed using a combination of one solvent in which your

compound is soluble at room temperature (Case A) and one in which your compound is not soluble at any temperature (Case B),

Procedure

add drops

of

solvent to the solid until the material is just barely dissolved. It's important

the warm

to use the minimum amount of solvent possible; the most common reason for failed

recrystallizations is using

too much solvent. After dissolving the compound, gravity filter the solution to remove any

insoluble impurities, and rinse the filter with a small the desired product.

Finally,

allow the liquid to cool slowly to room temperature. The more slowly it cools the more molecules have to order themselves into

crystal arrangement. If after

~10 minutes no crystals appear you can place the container in an ice bath to facilitate

crystallization.

To recrystallize a compound using a combination of two solvents (i.e. solvent A and B

above) you will need to warm small amount of each solvent. In this

case we'll use

ethanol and water as an example, because it is a common combination for mixed solvent recrystallization. Many organic compounds are soluble in ethanol, which can as our solvent "A" and many organic compounds

will serve as our solvent "B",

are insoluble in water, which

is used to separate

identity of an unknown compound.

of reactions, and 3) aid in determining the

How it works

TLC uses a stationary phase and a mobile phase. The stationary phase is made up

of an adsorbent, like silica, that is fixed to I surface. The mobile phase or eluent

is an organic solvent that passes over the stationary phase, carrying compounds

GSI will demonstrate how to develop and analyze a TLC

plate

in your lab section.

Predicting the order of elution We can make rough predictions about how far different compounds will travel Although size and shape also influence the

in ethanol

influence the distance traveled by using more

warm ethanol r "A"

or

you reach the saturation point of the compound. First add dissolved. Then slowly add drops of water

mixture turns slightly cloudy. Finally add a few additional drops of ethanol This ensures

that you have reached a ratio of warm ethanol:water that will dissolved the compound, but have used the smallest volume of solvent possible to achieve done this you can continue in the same manner

as

described above for single solvent recrystallization.

12

less polar compound

more

drops of ethanol to the solid until it is just

dissolution. Once you have

will have a

less polar solvents. For

example, if you want a more polar compound to travel further on the plate,

the first step is to alternate between adding warm ethanol and warm

until the cloudiness dissipates (the small particles of solid re-dissolve).

on the plate or the "order of elution."

distance traveled, we typically use polarity to predict the elution order.

The adsorbent is typically silica gel, which is quite polar. This quality means that very polar compounds

provided in later section.

until the

mixture i

compound i

spotted onto

placing it in a container with a small amount of solvent (eluent or mobile phase). While it develops, the solvent will travel up the plate and carry compounds with it. Individual compounds have different affinities for the adsorbent and eluent based on their polarity, size, and shape, which causes them to travel

more polar solvent (i.e., ethyl acetate) rather than less polar solvent (i.e., hexanes) as the eluent. Guidance for selecting solvents is

In this case

TLC plate, with silica adsobent layer acting as 'stationary phase

with it.

To prepare for TLC, a small amount of a compound or mixture is first spotted onto the stationary phase on a TLC plate. Then, the plate is developed by

you might select

water to your solid until

compounds based on

greater affinity for the adsorbent and spend more time on the stationary phase when the plate is being developed. Less polar compounds will have a lesser affinity for the stationary phase and travel farther on the plate. We can

crude product

warm H-O or "B"

of chromatography,

different distances on the plate and to be separated. TLC was introduced in Chemistry 211, and your Chemistry

Procedure for a mixed-solvent recrystallization

serve

(TLC) Guide

like all forms

to 1) evaluate the purity of :t product compound, monitor the progress

for single-solvent recrystallization

amount of additional warm solvent to minimize loss of

Thin layer chromatography TLC,

differences in properties like polarity, shape, and size. In Chemistry 216, you will use TLC as a diagnostie technique

To recrystallize a compound using a single solvent, slowly

chance the

Thin Layer Chromatography

13

polar compound

Calculating

Rf

FL.C is a qualitative technique. We can evaluate the purity or identity of a compound based on how far the compound travels on the plate relative to other compounds. To make more precise comparison, we can quantify the distance traveled by measuring the distance (with a ruler) and distance the compound traveled and om and the eluent traveled

calculating an Rf value. The Rf value is the ratio between the

Co-spotting technique

Co-spotting i It is the

For example, if a compound inthertkossinset.tnstihew.09ethecrRrensded.omtc.hamghndheromnupnaendgyravndesdl distance the

eluent (solvent) traveled.

TLC technique that we use to directly compare two compounds (or samples) on the

most basic and

the plate:

frequently used technique you should use routinely. We spot compounds 1) compound A, 2) compounds A & B together, and 3) compound B.

same

TLC plate.

on three "lanes" on

traveled

Spot the plate

When spottng

as

usual

Compounds A & B

the

are different

otting one compound,

2 cm

Rf of A = 2/3 = 0.67

wait for itto completely dry, then

1.5 cm

Rf of B = 1.5/3 = 0.5

reference for your i

Compounds A & B are the same ( similar

spot the second compound.

The center lane (A&B) sei

helptull your compounds

vo similar Rf values.

Rf value should always I

reported as a decimall

Selecting a solvent as the eluent for TLC A critical part of using TLC

selecting a solvent

as your

eluent (mobile phase). First, your compound

mixture

must be soluble in the solvent you select, and the solvent must be available in the lab. Second, your compound should be

sufficiently polar so as to attract the compound, carry it up the plate, and separate it from other compounds.

Sometimesmuke multiple solvents are used. The best solvent (or solvent mixture) is one that will give you good resolution. informed predictions about which

We

solvent or combination of solvents will work

ultimately have to evaluate the solvent empirically (try it out") to ensure it works.

best. Still.

Methanol

ill. Rxn 3

? material

isolated from

acetanilide

reaction

Ethanol Acetonitrile

mixture

standard

A

Acetone

another

"Dichloromethane

Chloroform

Diethyl Ether

Least Polar Toluene

"Hexanes'

In the examples above, plate i (reaction 1) shows that spots

*Good TLC solvents that are available in the 216 lab

hexanes. Dichloromethane is often

acetate, dichloromethane, diethyl ether, and good solvent to try first because oderately polar and dissolves most

ethyl acetate and hexanes are the most commonly used solvent system and work well in relative portions of ethyl acetate (relatively polar) and hexanes (relatively nonpolar) to achieve the desired separation of our compounds Often a suggested solvent or solvent mixture will be combination because you can adjust the

Ethyl Acetate

2:1

(polar)

Hexanes Ethyl Acetate

poorly resolved

better

14

Rf values. Because the

not yield the desired product. Plate ifi (reaction 3) shows spots with comparable Rf values in the middle of the plate,

reaction yielded the desired product. We also see a second spot at lower Rf in lane A, which indicates that an impurity present. Finally, on plate iv (also reaction 3), the reaction mixture is compared to the product standard and the starting material so that can more conclusively determine the identity of the impurity in lane

the

Because it has a similar Rf value to the lower spot in lane C (starting material), we can infer that the mixture

contains both

the desired product and unreacted starting material.

provided in your lab procedure. Sometimes you will need to select one or optimize the ratio of your mixture. Work systematically and adjust the solvent ratio until your TLC plate is well resolved. Hexanes (non polar) resolved

A and B have the same or similar

Rf values of the isolated material and the standard are similar, we can infer that the reaction likely yielded the desired With plate ii (reaction 2), we see that the Rf values are quite different, and can infer that the reaction did

product.

suggesting that

Common TLC solvents available in Chemistry 216 include ethyl compounds. Mixtures of

starting material aniline

(desired product)

*Ethyl Acetate*

middle of the plate anc are distinct from

TLC plates from four reactions are shown below.

we

Most Polar Hg0 (not a good solvent for TLC) Good resolution: the spots appear somewhere in the

Compare a reaction product to a commercially available standard We can use TLC to evaluate whether a reaction has produced the desired product and whether the product is pure.

1:1 Hexanes to Ethyl Acetate good resolution

15

Monitoring the progress of reaction Pinaily, we will use TLC to monitor the progress of the on

which you

Separations Guide

reaction. To do this, you can prepare:

series i f TLC plates

co-spot a standard of the desired product of the reaction (©), the reaction mixture (B), or the starting

material (A) and develop the plate. You then repeat this intervals in the reaction. For example, at the start of the reaction, you might expect to see that the reaction mixture has a spot with an Rf value that is comparable to the starting material standard (plate i). As the reaction progresses, may that starting material spot is still the present but that a new spot appears that corresponds to the product standard (plate ii). Finally, when the starting material spot disappears, the reaction is complete (plate iii).

Extraction and washing are two primary separation techniques used by organic chemists to separate product compounds from solvents, impurities, and side products after reaction is completed. Extraction and washing are

essentially

the same technique with different goals. The goal of extraction is to extract your desired product compound from your reaction mixture containing impurities. The goal of washing is to wash impurities from the

mixture, leaving purified product behind. Using a separatory funnel

Chemists typically use a special piece of glassware called a separatory funnel to

. 1 min elapsed

ii. 30 min

elapsed

ili. 1 hour elapsed

reaction mixture

cyclohexanone

standard

A B

Density table: Solvent Water (H2O) Diethyl ether

ABC

(desired product)

Comparing an unknown compound to standard compound to determine it's identity We can use ILCI

gather evidence that helps us determine the identity,

an unknown compound. You need to have

access to a standard sample (lane B) of the compound you think you have so

that 1

1 compare it t

the unknown

sample (lane A). If the Rf values of both spots are similar, that along with other data (i.e., NMR or IR spectra), can be used to determine the identity of your unknown.

stopper

2

Density g/cm 0.999

0.713 1.327 Dichloromethane Tetrahydrofuran (THF) 0.888

Hexanes

0.661

Ethyl acetate

0.902

top layer, lower density liquid

bottom layer,

higher density liquid

A crucial note: Never dispose of a layer until you are

you'll never need

it again. You can easily mistake which layer your product is in, and once you put it in the waste, you can get it back!

?

To set

unknown compound

Two

have a greater affinity for based on these characteristics. This will help you decide which layer to keep. Chemists build an intuition about this with practice, and your GSI can help you think this through.

B

cyclohexanol

conduct an extraction or wash.

immiscible liquids are introduced into the funnel and will form two layers (figure 1). The liquid with the lowest density will float on the top. This means you can use density to determine which layer is which (see the density table for common organic solvents below). The characteristics of your product compound and the impurities, for example, their overall polarity, whether they are charged or neutral, and their capacity to form hydrogen bonds, can be used to predict which liquid layer a given compound will end up in. You have to decide which solvent the compounds vill

acetanilide standard

up the separatory funnel, begin by attaching a ring clamp

the bars

in the back of your hood or to a ring stand. Next, place your funnel in the ring and put a clean container (beaker or vial) under the funnel. You will need

at least two clean containers ready to collect each layer. Keep one container under the

beaker

funnel at all times to ensure you don't lose anything if something

goes wrong. Ensure the stopcock is always horizontal (closed) except when venting the funnel (more on this below). When ready, carefully add your two

liquids and your reaction mixture as indicated in your experimental procedure. One liquid is typically water, and the other is pure organic solvent that is immiscible in water. One layer

should float on top of the other.

Once your liquids are added you need mix them allow the impurities and product to migrate to the layer they most affinity. That means they will either stay in the reaction mixture liquid or migrate to the pure solvent. To mix them, place the stopper at the top of the funnel. Prepare to lift the funnel out of the ring stand. Place one hand

have the

top of the stopper to secure it and place the other hand on the lower part of the funnel in a way that allows support it and manipulate the stopcock as needed. Carefully lift the funnel and invert it so that the stem is pointed at an upward angle. The funnel stem should be pointed into your fume hood. Gently swirl the liquids while venting. As you swirl, solvent vapor can build up. So, it is necessary periodically by carefully turning the on the

you to

stopcock intermittently while swirling. You may hear the gaseous solvent leaving from the stem, particularly

17

mere volatile solvents like diethyl ether. Repeat the gentle swirling with venting stopcock is in the closed position and replace the funnel on the ring stand.

two more times.

Make sure the

Apply what you have learned 1)

Evaluate the solvent pairs below and decide which solvent would form the top layer in your separatory funnel. Circle the solvent that will

Remove one liquid layer

from the funnel by slowly turning the

stopcock to open and toggling to close to control the flow rate.

Carefully watch the line between the layers o ensure that you stop before you get to the second layer. Add additional pure solvent and

repeat the

extraction two more times by again swirling and venting layer of solvent. Once you have extracted (or washed) your product 3 times, you combine the layers and remove the

with the

solvent as directed.

be

on top.

a.

Diethyl ether

b.

Dichloromethane

and

C.

Tetrahydrofuran

and

and

water

2) Evaluate the Lewis structures of the solvents, product compound, and impurities shown below and draw a

line between

the molecules and the solvent layer you expect it to migrate to during mixing. Keep mind characteristics including overall polarity, whether they are charged or neutral, and their capacity to form

hydrogen bonds, can be used to predict which liquid layer they

classmate.

CH3CH2OH diethyl ethor

Na

OCH2CH,

separatory at both the top and bottom. making

sure to support the stopper

wert the funnel

r hood to

prepare for venting.

18

19

will end up in. Discuss your

infrared Spectrosco y Tabie Functional Group Na Alv

cm1)

Shape and Intensity

C-H 2960 – 2850

ht SeVed p

H .

H t

C-H 3080-3020

„H

HgC

Sharp, meaI n uI On

C=C 1620-1680

Sharp *

C-H 3100-3000

Sharp, strong

C=C 1600-1580

Sharp, strong

1-Prop n

-CEC-CH Propyn

Aromatic Rings H

H

1C e

c

H. H*

*C

c"

Ber

-

c

0 -H

H

-

0-H

Men

ylic Acids

Formic acid

Wpt0II

.

0-H 3000-2500

Rro

C=0 1725-1700

Sharp, very strong

C=0 1725-1705

Sharp, very surong

C=0 1685-1665

Sharp, very strong

Acetone

HgC "CHg

1.ro-CH

H C

3-Penten-2-one

Nuclear Magnetic Resonance Spectroscopy Table Functional Group Names & Example Compounds

Absorption Ranges (cm-) (single absorption unless noted)

Aldehydes

C=0 1730-1720

C-H 2900-2800 Ethanal

Shape and Intensity

Sharp, very strong Sharp, variable

& 2750-2700 (2 peaks)

Type of Hydrogen Atom

Type of Hydrogen Atom

RCH3

0.9

RCH2R

1.3

cyclic R3CH

7.3

1.5

1.5-2.0 1.8

Esters

CH3 Methyl formate

H.C

C=0 1750-1740

Sharp, very strong

C-O 1300-1000

Sharp, medium

R'

RCH 2.0-2.3

RNH2

RCCH3

3-5

2.3

Ethers

C-O 1300-1000

Sharp, medium

Diethyl ether

RCNHR

CH3

Amines (primary)

N-H 3500-3300

Sharp, medium

(two peaks)

CECH

2.5

RNHCH2

2-3

RCH2X (X= CI, Br,

3.5

ROH

1-5

3.8

Ethylamine

Amines (secondary)

ROCH&,RCOCH3 N-H 3500-3100

Sharp, medium

(one peak)

R2C=CH2

5.0

RCH=CR2

5.3

10-13

RCOH

CH3

H.C

H

13C NMR

N-Methylethylamine

Nitriles

Type of Carbon / RCH2CH3 C=N 2300-2200

Sharp, variable

RCH2CH3

R3CH

H-C-CEN

125-150

25-38

~20

Sharp, strong

& 1385-1345

RCOCH3 RCH2CI

Nitromethane

RCH2Br N-H 3500-3350

Sharp, medium

C=0 1680-1650

Sharp, very strong

RCH2NH2 RCH2OH RC=CH

RC=CH Methanamide

125-140 117-125

RCCH3 N=0 1560-1515

Amides

RCEN

16-25

~30

Methanenitrile

Nitro Groups

Type of Carbon Atom

RCH=CH2 13-16

RCH=CH2

170-175

RCOR

40-45

177-185

28-35

RCOH

37-45

190-200

50-64

RCH

67-70

74-85

205-220

RCR

115-120

25

II. (20 points)

1 (20 points)

A The tollowing reaction was recently reported (J. Am, Chem. Soc. 2015, 137, 11246). Using the information provided following questions.

below, please answer the

OSO-CFs

A. In the synthesis of acetanilide, 0.03 moles of aniline were treated with 1.2 molar equivalents of acetic anhydride this information, please answer the questions below:

Given

Pd(OAc)2 (4 mol %)

t-BuPHOX (10 mol %) CH2Cl2

toluene, 95 °C

Molecule: MW

316.29 g/mol

Pyrrolidine Lithium tert-butoxide MW 71.12 g/mol 80.08 g/mol density = 0.852 g/mL

Aniline

Product 2

93.13 g/mol

= 237.35 g/mol

Acetic Anhydride 102.99 g/mol molar equivalents

MW

molar equivalent 0.03 moles

This reaction was conducted using: 320 mg of Molecule 0.099 mL of pyrrolidine 1.4 molar equivalents of Lithium tert-butoxide

(a) Calculate the mass (in

Acetanilide 135.16 g/mol

(b) Calculate the

of

theoretical yield (in

acetic anhydride that was added to

of acetanilide in this

the reaction mixture. Please round to

The reaction formed 231 mg of Product

reaction.

two decimal places - X.XX g.

Please round to two decimal places - X.XX g

(a)

Calculate the amount, in moles

of molecule

that was used in this

(c) This reaction afforded 2.67 g

reaction.

of acetanilide product. Calculate the percent yield of this reaction.

5

Please round to four decimal places X.XXXX moles.

(b) Calculate the amount, in moles, f pyrrolidine that was used in this reaction. B

Please round to four decimal places - X.XXXX moles.

The acetanilide you hi

ynthesized is to be examined for new, undiscovered, biological activity. For this

experiment to be conducted, you mi to afford a 0.1 Molar solution.

take 0.1 g of acetanilide and dissolve it in dimethyl sulfoxide (DMSO)

(c) Calculate the mass, in grams, of lithium tert-butoxide

Calculate the amount of dimethy! sulfoxide solvent

that was used in this reaction.

(in mL) required to prepare a 0.1 M solution of acetanilide starting with 0.1g of acetanilide. Please

Please round to three decimal places . X.XXX g.

d) Calculate the

round to two decimal places - X.XX mL.

yield

of Product :

Please round to

two significant figures - XX%

28

29

11. (14 points)

II. (20 points)

A. In the synthesis of acetanilide, 4 mL of aniline

information, please answer the questions below:

treated with 1.2 molar equivalents of acetic anhydride. Given this

A. In the

synthesis of ethyl benzoate, 1 g of benzoic information, please answer the question below:

is

dissolved in ethanol at a concentration of 0.2 M. Given this

H2SO4

HO Aniline

MW = 93.13 g/mol d = 1.022 g/mL

Acetic Anhydride

MW = 102.99 g/mol

Acetanilide 135.16 g/mol

= 1.08 g/mL

(a) Calculate the volume (in mL) of

(b)

5

B Rank the

MW = 150.18 g/mol

reaction.

This reaction afforded 2.8 g

acetanilide product. Calculate the percent yield of this reaciton.

Ethyl Benzoate

MW 46.07 g/mol I= 0.789 g/mL

122.12 g/mol

(a) Calculate the volume of ethanol (in mL) used in the

acetic anhydride that was added to the reaction mixture.

Ethanol

Benzoic Acid MW

catalytic

CH3

(b) If the reaction provides ethyl benzoate in an 80% yield, how

5

much ethyl benzoate i produced by the reaction (in g)?

following compounds in order of increasing carbonyl stretching frequency B. Rank

A

C

the following compounds in order of increasing carbonyl stretching frequency

NH2

write the correct letter in e: A

B

write the correctletter in each box

highest wavenumber stretch

lowest wavenumber stretch

highest wavenumber stretch

30

lowest wavenumber stretch

31

6

Water

MW = 18.0 g/mol d = 1.00 g/mL

III. (15 points)

IV. (20 points) A. For the structure and IR spectrum shown below,

carresponding streches in IR spectrum.

match the labeled carbonyl groups on the molecule

with the

Number Letter

A. Your friend is

process of

pharmacist, who has made a serious mistake, and needs your help to fix it. During

stocking small bottles from larger ones, samples of Cardizem (a calcium channel blocker used to treat hypertension and angina) and caffeine were placed into unlabeled bottles, and then accidentally mixed up. Fortunately, you can figure which substance is in which bottle using IR spectroscopy. Given the IR data below (one spectrum is caffeine and the other is Cardizem), write the letter corresponding to a specific carbonyl group in either caffeine or Cardizem next to the

frequency of the IR stretch that corresponds to the carbonyl in the box below.

Hint: if two or more carbonyls appear to be structurally similar, be sure to think carefully about resonance when

making your assignments.

IR Spectrum 2

IR Spectrum 1 A: 1766 cm-1

B: 1723 cm71

1699 cm-t

1743 cmt

1659 cm-

1679 cm-t

1671

(H3C)2N Cardizem

r corresponding with stretching frequency

Caffeine

Hint: 1715 cm7i 1727 cm7

B

B. An experimental procedure indicates that an organic product should be extracted from water into dicholoromethane (CH2C12). Given the density of water (1.0 g/mL) and dichloromethane (1.33 g/mL), indicate which layer in the separtory funnel is water, and which is dichloromethane.

A student conducting the reduction of ketone A to alcohols B and C monitored the reaction by TLC. A drawing of a

TLC plate is shown below. In lane 1 of the TLC plate the student spotted an authentic sample of pure ketone A. In lanes 2-4 the student spotted a sample from the reaction mixure at time intervals of 15 min, 30 min, and 1 h from the start of the reaction. Given the data below

answer the following questions.

The top layer is

3 cm

circle one): Water CH2Cl2

The bottom layer is (circle one): Water

CH2Cl2

21

NaBH4

CH;CH2OH C.

(minor)

(major)

Based on the TLC data shown below, answer the following questions.

lane 1 = A lane 2 = rxn mix @ 15 min

Lane

lane 3 = rxn mix @ 30 min

(a) How much time is needed for the reduction of A to proceed to completion (i.e., no starting material remains)? 15 min

< 15 min

60 min

30 min

.6 cm

(b

min

boxes provided below.

B

and C are (circle one answer)

different conformations

the same molecule

constitutional isomers B

Hi value

enantiomers Hi value

diastereomers

returned only starting material; no product was formed

The starting material was completely consumed, but no product

(c) What is the relationship between products B and

and major product B and enter the values in the

Based on this TLC, which of the following statements is true (circle one).

The reaction

circle one answer

(b) Calculate the Rf ralues for starting material A

= starting material

Lane 2 = sample from reaction mixture Lane 3 = authentic sample of desired product

lane 4 = rxn Mix @ 60 min

(a) What is the Re of the desired product (TLC lane 3)?

The product was formed, no side products

material remains. • The

was

formed

are present, but some unreacted starting

starting material was completely consumed, desired product was formed,

and side products were also formed.

The starting material was completely consumed,

formed

33

and only desired product was

B. Based on the TLO data shown below, answer the following questions.

B. The reduction of benzophenone with NaBH , was carried out, and the resulting alcohol product was purified by

column chromatography Four fractions were collected from the column, and these were analyzed on the TLC plate

Passible Unknown Lane

shown below.

= aniline

Lane 2 = unknown aniline derivative 2.8 cm

NaBH,

CH;CH2OH

(a) Which spot on the TLC plate corresponds to he ketone starting material (circle one)?

(a) What is the Rip of the

(b) What

unknown aniline (TLC lane

aniline (write the compound number i

structure in the chart above corresponds to the unknown

B

A

below)?

(b) Which fractions contain (circle all that apply)?

the alcohol

3 cm

2 cm

The esterfication of p-chlorobenzaldhyde with ethanol wascarriedout,and by column chromatography Four fractions were collected from the column

shown below

(c) Calculate the Rf values for both spots (A and B)

resulting ester product was purified these 1 analyzed 1 the TLC plate

and

enter the value in the boxes provided below B

HgSO4 CHaCH2OH

OCH-CH3 + H.O

Af value

(a) Which spot on the TLC plate corresponds to the carboxylic acid starting material (circle one)?

4 cm

B

The reduction of propiophenone was carried out Upon completion the reaction

aqueous mixture

was extracted with ethyl acetate.

quenched with water and the

A

CH,CH:OH

(b) Which fractions contain the ester product (circie apply)?

During the extraction procedu

B

Rf value

(c) Calculate the Af values for both spots (A and B) and enter the value in the boxes provided below.

organic

(ethyl acetate) layer

which layer will be on the bottom (circle one)? ethyl acetate and water will not separate into two layers

aqueous

(water) layer

B

Ht value

Rf value

After the organic layer is removed from the aqueous layer

this remove from the organic layer (provide a structure

35

3

stirred with magnesium sulfate What word answer)?

does

1S)

CI I WIve In Speclra DelOw Wion thne corresponding compounds in tne fadle. Inaicale your diSWel Dy piacng

0 CH O (solvent)

IR. 1740 cm "oCH

a ||

to s o ).1II

HC. Hjć

IVI

* CH

tI▇ ▇

▇uI- - ▇ talI 1 ▇

▇ IV,V-uII I U al

IU ▇

▇

II W,Il

SaI y""

I(12ponis

p

DuNVIVne1I a M N VV1LILII

1 tT

Compound

tt▇

▇ LC

▇

1T ▇ ▇

1▇ ▇

▇▇

Match the four NMR spectra below with the corresponding compounas in Ue laDie. Iucate your cnowcr ) piow

Sompound

, o

CH

e

Mtch the NMR spectra DeOW WI tFe cUr p unmg 11

p uT u▇ tTe teI ▇ T GTate y ▇ anTouvGt ▇

Spectrum Number

*po

ich the four NMH spec

Cnetri nn nunnla

3H, S

. i,

.O 3H, t

C T

d. 1H t, T t, 1H|d, 1H

,

t d, 1

H, s

3H, s

3H, s

d. 1

d,

r in t

nn

ri ta

1. (15 points) Match the

I. (15 points)

five NMA spectra below with the corresponding compounds in the table. Indicate your answer by placing

the spectrum number in the appropriate space. Spectrum number

Spectrum 1:

Match the five NMR spectra below with the corresponding compounds in the table. the spectrum number in the appropriate space. Spectrum

Compound Structure

number

Indicate your answer by placing

Spectrum 1

Compound Structure

m, 2

m. 2

Spectrum

Spectrum 3

Spectrum

Spectrum 4:

Spectrum

m, 2

m,

t, 3

Spectrum 5

m, 1 m, 1 m.

44

*

*|

Match tne five NMR spectra Delow Wiln tne corresponang copounas In tne table, Inalcate your answer by plad

poln

Match the fivenumber C NMR inspectra below withspace. the corresponding compounds in the table. Indicate your answer by piacing the spectrum the appropriate Spectrum

Con

)=

h

00-

16o14o

0 14o

Spectrüm .a

Spectrum 5

I. (15 points)

1. (15 points)

Match the five C NMR spectra below with the corresponding compounds in the table Indicate your answer by placing the spectrum number in the appropriate space. Spectrum 1:

Spectrum number

Compound Structure

Match the five C NMR spectra below with the corresponding compounds in the table. the spectrum number in the appropriate space. Spectrum number

Compound Structure

Spectrum 2:

Spectrum 3:

Spectrum 2:

Spectrum 4:

200 180 160 14

Spectrum 3:

Snectrum

Spectrum 5:

Snartrum

48

Spectrum 1:

Indicate your

by placing

1. (15 points)

II. (x points)

Match the five C NMA spectra below with the corresponding compounds the spectrum number in the appropriate

space.

table. Indicate

your answer by placing A. For each of the compounds below predict

Spectrum 1:

Spectrum Compound Structure number

the number of peaks (ignore coupling) in the 1H and 13C NMR

spectra.

Proton NMR: Number of Peaks

Ratio of Peaks

Carbon NMR: Number of Peaks

H3C,

Proton NMR: Number of Peaks

Ratio of Peaks

Spectrum 2:

Carbon NMR:

Number of Peaks

Proton NMR: Number of Peaks

Ratio of Peaks

Carbon NMR: Number of Peaks

Spectrum 3:

Spectrum 4:

B. NMR spectroscopy is a useful tool for analyzing mixtures of compounds, as integration can be used to determine the ratio of products present in

mixtures. A proton NMR spectrum was obtained for the mixture of A, B,

and D shown

below. This spectrum showed four single peaks, one for each of the components. The peaks were integrated, and the observed ratios are also provided below. Given this information, answer the following questions: CH3

H3C-Si-CHs

HaC-CEN

HaC CH3

CHa C

B

Chemical Shift:

Integration ratio:

2.10

3

2.62

12

Spectrum 5:

a. Which compound is present in the largest amount

(the highest molar concentration). Circle the letter that corresponds to your answer.

b. Which compound is present in the smallest amount (the lowest molar concentration). Circle the letter that corresponds to your answer.

A

D

3 50

51

Page 2 A. For each of the compounds below predict the number of peaks in the 1H

I1. (15 points)

and 13C NMR spectra. A.

'H NMR:

For each of the compounds below predict the number of peaks (ignore coupling) in the H and 13C

13C NMR:

Proton NMR: Number of Peaks

13C NMR: CH

1H NMR:

Ratio of Peaks

Carbon NMR: Number of Peaks

3 Proton NMR: Number of Peaks

1H NMR:

13C NMR:

13C NMR:

Ratio of Peaks

Carbon NMR: Number of Peaks

Proton NMR: Number of Peaks

B. NMR spectroscopy is a useful tool for analyzing mixtures of compounds, as integration

determine the ratio

NMR spectra

'H NMR:

products present in mixtures. A proton NMR spectrun

A, B, C, and D shown below. The peaks corresponding to each compound

can be used to was obtained for the mixture of

Ratio of Peaks

Carbon NMR: Number of Peaks

vere integrated, and the observed questions.

ratios are also provided below. Given this information, answer the following

3. NMR spectroscopy is a useful tool for analyzing mixtures of compounds, as integration can be used to determine

the ratio of products present in mixtures.

Chemical Shift:

A

B

3.2

3.53

A proton NMR spectrum was obtained for the mixture of A, B, C, and D

shown below. This spectrum showed four single peaks, one for each of the components. The peaks were integrated, and the observed ratios are also provided below.

1.11, 3.56, 5.19

Given this information, answer the following questions:

4.8 H.C

Integration ratio:

CH2Cl2

HaC-CEN

9:6:3

10

Chemical Shift:

2.17

5.10

2.10

Integration ratio:

9

a. Which compound is present in the largest amount (the highest molar concentration). Circle the letter that corresponds to your answer.

ABCD

b. Which compound is present in the smallest amount (the lowest molar concentration). Circle the letter

corresponds to your answer.

c

a. Which compound is present in the largest amount (the highest molar concentration). Circle the letter that corresponds to your answer. that

D

3

D b.

Which compound is present in the smallest amount

(the lowest molar concentration). Circle the letter that corresponds to your

52

B

11. (21 points)

I. (20 points)

A. For each of the compounds below predict the number

CH3

of peaks (ignore coupling) in the 1H and 3C NMR spectra.

Proton NMR: Number of Peaks

A. For each of the compounds below predict the number of peaks

Ratio of Peaks

(ignore coupling) in the 'H and 13C NMR spectra

Proton NMR: Number of Peaks

Carbon NMR: Number of Peaks

Carbon NMR: Number of Peaks

Proton NMR: Number of Peaks

Ratio of Peaks

Proton NMR: Number of Peaks

Carbon NMR: Number of Peaks

Carbon NMR: Number of Peaks

OCH3

Proton NMR: Number of Peaks

Proton NMR: Number of Peaks

Ratio of Peaks

Carbon NMR: Number of Peaks

Carbon NMR: Number of Peaks

5 B. For

the structure and NMR spectrum shown below, match the labeled hydrogen atoms on the molecule with the

corresponding signals in the proton NMR spectrum.

B. For the structure and NMR spectrum shown below, match the labeled hydrogen atoms corresponding signals in the proton NMR spectrum.

Number Lettel

molecule with the

E

B s,3

Number Letter

CH3

D

F

s, 3

S, 3

B

t, 2

d,2 d,2

C

6

broad,

54

55

I1. (21 points)

II.

A. For each of the compounds below predict the number of peaks (ignore coupling) in the

Proton NMR: Number of Peaks

H and 13C NMR spectra.

(20 points)

A. For each of the compounds below predict the number of peaks (ignore coupling) in the 1H and 13C NMR spectra

Ratio of Peaks

Proton NMR: Number of Peaks

Ratio of Peaks

CHa

Carbon NMR: Number of Peaks

CH3

OH

Proton NMR: Number of Peaks

Ratio of Peaks

CH3

CH3 CH3 CH3

Carbon NMR: Number of Peaks

Proton NMR: Number of Peaks

Ratio of Peaks

Carbon NMR: Number

I Peaks

Proton NMR: Number of Peaks

Ratio of Peaks

Carbon NMR: Number of Peaks

Proton NMR: Number of Peaks

Ratio of Peaks

CHg

Carbon NMR: Number of Peaks

CHa

: For the structure and NMR spectrum shown below, match the labeled hydrogen atoms on the molecule with the

corresponding signals in the proton NMR spectrum.

Carbon NMR: Number of Peaks

B. For the structure and NMA spectrum shown below, match the labeled hydrogen atoms on the molecule with the

corresponding signals in the proton NMR spectrum.

B

Number

C Letter

Letter

CH3

D B

D

m,1

C

E

HSP-41-39

pom 56

m, 2

E m, 2

2 c II. Name

A. For each of the compounds below, predict the number of peaks in the 'H and 13C NMR spectra. B. For the bolded hydrogens in each molecule, indicate whether these equivalent (will both appear as one signal), or not equivalent (will appear as different signals).

I1. (18 points) A. For

each of the compounds below predict the number of peaks (ignore coupling) in the 1H and 13C NMR spectra

Circle the correct answer.

Proton NMR: Number of Peaks

Carbon NMR: Number of Peaks

OCHa

OCH3

'H NMR: Number of Peaks

13C

NMR: Number of Peaks

equivalent not equivalent

Proton NMR: Number of Peaks

1H NMR: Number of Peaks OH

Carbon NMR: Number of Peaks

13C NMR: Number of Peaks

equivalent not equivalent

B. For the structure and NMR spectrum shown below, match the labeled hydrogen atoms on the molecule with the corresponding signals in the proton NMR spectrum. NOTE: The H-atom attached to oxygen is not visible due Ic broadening.

HaCO

1H NMR: Number of Peaks

D

13C NMR: Number of Peaks

5

equivalent

not equivalent

Number

S,

H3C

C. For the structure and NMR spectrum shown below, match the labeled hydrogen atoms on the molecule with the corresponding signals in the proton NMR spectrum.

Number

Letter

d, 3

A

10 B

m,

m, 1

D

m, 2 2 pts each

58

C B

t, 2

E

the bolded n alogens In eacn mO18cule, Inalcale Wn urer tnese are equivalent (WIII DO n appea

jgnals). Circle the correct answer. (1 poi

IV. (20 points)

Provide the structure of a molecule with the chemical formula CsHe

below

H

NVM

CH,

ČH,

|

IR: 3061, 2947

CH3

m

WValent

the NMR signals (letters) to the numbered protons in the structure belo

13C NMR

33 2 3 4 5

6 8 2 t, 4 T y uIIIS or

C Hg0?

S, 2, br

" e

ta and the I R

IV. (20 pon

( UpoII

Provide the structure of a molecule with the chemical lormula CjH 20, that is consistent with the NMR spec

Provide hel0W. the structure of a molecule with the chemical formula CyH40, that is consistent with the NMR spectra shiown 1 NMH

1

IR: 3020, 2913, 17 16 Cm

1739 Cm

d, 2 d, 2

13C NMR

eaks (numbered below)

98

yL A

CyH 20,?

functional group

hase0 OI U 1

NMR data and the IR

for mo1e u

CH03

What functional goup 1

1

U

I

I I(

IV. (20 points)

Provide

B For

the structure of a molecule with

the chemical formula C13H 16O2 that is consistent

with the NMR spectra shown

below.

not

the bolded hydrogens in each molecule, indicate whether these are equivalent (will both appear equivalent (will appear as two different signals) Circle rect answer (1 point each)

as

one signal),

d, 6

IR: 3085 (br), 2953, 2869, 1708 cm-1

Note: There is also a broad signal at

d, 3

12 ppm with an integration of 1 H

equivalent

equivalent

equivalent

d,2

9.1

not

equivalent

not equivalent

not

equivalent

13C NMR 10 peaks (numbered below)

B. Based on the proton NMR spectrum and IR

1 shown below (for the product), draw the complete Lewis structure of

the product formed in the following reaction (no generic "R" groups - draw

6+7

I structure).

PPh,

CH>Cl2

8

Product structure

H NMR and IR data for Product IR: 1722 cm-1

200

180

100

60

COG-13-:

d, 2

How many units

of unsaturation for molecule

S.3

C13H18O2?

What functional group(s) are present based on the

NMR data and the IR stretches labeled above?

structure

64

for CyyH1gOg that fits the data above 10 65

* |IU po

(0p

Provide the structure of a molecule with the chemical formula C H 00, that is consistent with the NMR spectra sho

Provide the structure of a molecule with the chemical formula C H0, that is consistent wih

belo

1 NM

IR: 1770 cm-1 atl

1 C NMR

so

U

IV. (10 points)

IV. (20 points)

Provide the structure of a molecule with the chemical formula CgH120 that is consistent with the NMR spectra and the IR data shown below.

Provide the

structure of a molecule with the chemical formula C5H10O that is consistent with the NMR spectra

shown

below.

m, 2

'H NMR

m, 2

IR: 3328 cm-1

m, 2

m, 2

n, 2

'H NMR

IR: 2960, 2719, 1728 cm-1

S,

HSP-43-200

d, 2

ppr

13C NMR 1 peaks (numbered below)

13C NMR 6 peaks

200

200

160

140

120

100

80

60

How many units

of unsaturation for molecule

C5H10O?

What functional group(s) present based on NMR data and the IR stretches labeled above?

structure for C6H120 that fits the data

68

10

structure for C5H1oO that fits the 69

data above

10

po

Provide the structure of a molecule with the chemical formula C NO that is consiSlent Witn the NMR Spectra and tne l a 0 aa

Page S u

enoctra shoW bel0W. H NMR

IR 1 , m & Z

,

, 17 14 CI1

a

*.ii e

C NMR

IR: 2958, 2872 cm C NMR -

WV

ANv

(19

IV. Name:

3 C

points)

Provide the structure of a molecule with the chemical formula C-H-NO that is consistent with the NMR spectra and IR data shown below.

IlI. Name:

Provide the structure of : molecule with the chemical formula spectra and IR data shown below.

CoH,BrO that is consistent with the NMR

IR: 3375, 2925, 1650, 1606 cm IR:

2925, 2855, 1698 cm-1

t, 3H

a, 2H

s, 1H . 1H

1H.

.1H

11C NMR 8 peaks labeled below

13C NMR 9 peaks labeled below

2 36

220

180

140

200 180

120

How many units

How many units

of unsaturation

of unsaturation for molecule

for molecule

140

120

100

80

60

40

C,H,BrO?

C.HgNO?

Indicate (name or draw)

Indicate (name or draw) one

160

8

one functional group present in the molecule based on the NMR data and the IR strectches

functional group

present in the molecule based on the NMR data and the IR streciches

structure for CyHgNO that fits the data above 10

labeled above?

72

labeled above?

structure for CgH-BrO that fits

73

the data above 15

IV. (19 points) Provide the structure of a molecule with the chemical formula G8H1402 that is consistent with the NMR spectra shown below

TH NMR

d, 61

IR: 1725, 1661 cm-1

d,2

0,3 d, 1

13C NMR

peaks (numbered below)

180

160

100

30

CDS-01-069

(a) How many units of unsaturation

(d) Draw the structure of the molecule

molecule CgH14O2? (b) What functional group is present

a macmillan learning

based on the IR stretch at 1725 cm

and the C NMR signal at 167 ppm? (C)

curriculum solutions

What functional group is present based the IF stretch at 1661 cm

and the

NMR signals at 123 and 144 ppm?

10 g1

3

structure for CgH1402 that fits the data above

10