Question 1

Predict the major organic product of the reaction. If you believe no reaction would occur, write NR.

Accepted Answer

The starting material consists of two esters, each of which will react with the amine to form an amide.

Question 2

Outline a synthesis for the transformation using the indicated starting material and any other organic reagent containing two carbons or less. You may also use any inorganic reagents and solvents you might need. Show the structures of all intermediate compounds. Reaction mechanisms are not necessary.

Accepted Answer

Working backward, the product has added a carbon to the starting material. The product is an amide, so the precursor might have been a carboxylic acid. The precursor to a carboxylic acid could have been a Grignard with CO₂. The Grignard would come from an alkyl halide, which could come from the addition of HBr to the starting alkene.

Note that the starting material contains a carbonyl that is not changed throughout the synthesis, but would be reactive with the Grignard reagent, so it needs to be protected. The synthesis in the forward direction would be:

Question 3

A student is asked to monitor the reaction by infrared spectroscopy. Explain what peaks the student should use to monitor the reaction (appearance and disappearance).

Accepted Answer

The reaction is a nitrile hydrolysis. A nitrile has a CN stretch at 2200-2250 cm^-1 and the student should monitor for disappearance of the nitrile stretch and appearance of a carboxylic acid stretch. The carboxylic acid will have a carbonyl stretch at ~1710 cm^-1 and a strong OH stretch at 2400-3000 cm^-1.

Question 4

Which reagents could be used to synthesize PhCOOH?

Accepted Answer

A)  PhCO2CH3 in acidic methanol 
B)  PhCOCl + LiAlH4 followed by treatment with acid 
C)  PhCO2CH3 in aqueous base followed by treatment with acid 
D)  More than one of these would work. 
E)  None of these would work. 
A)  PhCO2CH3 in acidic methanol 
B)  PhCOCl + LiAlH4 followed by treatment with acid 
C)  PhCO2CH3 in aqueous base followed by treatment with acid 
D)  More than one of these would work. 
E)  None of these would work.

Question 5

Given the synthetic sequence, predict the structures of the intermediate A and product B.

Accepted Answer

There is only one equivalent of acetic a

Question 6

Predict the major organic product of the reaction. If you believe no reaction would occur, write NR.

Accepted Answer

The thionyl chloride reacts wi

Question 7

When these two amides undergo hydrolysis under identical reaction conditions, it is found that amide A reacts significantly faster (>1000 times) than does amide B.
a. Draw the structure of each hydrolysis product in the appropriate box.
   b. Using concepts developed in this course, and using structures and reaction coordinate diagrams, explain the above indicated difference in the hydrolysis rates. (Assume the ring strains in amides A and B are essentially equal, and the tetrahedral intermediates (TIs) for both reactions are of about equal energy.)

Accepted Answer

a. Each reaction is going to hydrolyze t

Question 8

The Ritter reaction is a useful method for producing substituted amides. Provide a detailed, arrow-pushing mechanism for the transformation. Show all reactive intermediates and all proton transfer steps. (It is not necessary to show every resonance structure for intermediates.)

Accepted Answer

The nitrogen in the product must come fr

Question 9

Provide a detailed, arrow-pushing mechanism for the transformation. Show all reactive intermediates and all proton transfer steps. (It is not necessary to show every resonance structure for intermediates.)

Accepted Answer

This is a transesterification

Question 10

Draw a triglyceride formed from glycerol and three molecules of stearic acid (CH3(CH2)16COOH).

Accepted Answer

The glycerol has three hydroxy

Question 11

Predict the major organic product of the reaction. If you believe no reaction would occur, write NR.

Accepted Answer

An organolithium rea

Question 12

Predict the major organic product of the reaction. If you believe no reaction would occur, write NR.

Accepted Answer

Alcohols will react

Question 13

An unlabeled flask contains a compound with a molecule mass of 86. The 1H NMR data are F1F1F1S1F1F1F10 2.10 (pentet, J = 7.1, 2H), 2.30 (t, J = 7.1, 2H), and 4.30 (t, J = 7.1, 2H). The 13C NMR data are F1F1F1S1F1F1F10 22.5, 27.9, 68.8, and 178.1. The compound gives a positive hydroxamate test. Deduce the structure of the unknown compound.

Accepted Answer

The proton NMR data show only aliphatic

Question 14

Outline a synthesis for the transformation.

Accepted Answer

There are no reagents that can directly

Question 15

When the mixed carbonate below is treated with an excess of ethyl magnesium bromide, the indicated tertiary alcohol is formed in high yield. Write a detailed reaction mechanism for the first step of the reaction. Label "end of step 1" at the appropriate location. Indicate all organic products including by-products at the end of step 2.

Accepted Answer

Recall that a Grignard reagent can add m

Question 16

Describe the equilibrium constant for the reaction.

Accepted Answer

A) K > 1 B) K < 1 C) K = 1 D) can't determine K without knowing heats of formation A) K > 1 B) K < 1 C) K = 1 D) can't determine K without knowing heats of formation

Question 17

Draw a structure for these carboxylic acid derivatives.
a. propyl 4-ethylbenzoate
b. N-ethyl-N-methylpentanamide
c. cyclohexanecarbonyl chloride

Accepted Answer

a. The -oate suffix indicates an ester.

Question 18

a. Provide arrow-pushing mechanisms for the reaction. Clearly show all intermediates.
   b. If you wanted to reverse the transformation, what reagent(s) would you use? No reaction mechanism is necessary.

Accepted Answer

a. Sodium hydride will deprotonate the h

Question 19

Choose the best reagent(s) for carrying out the conversion.

Accepted Answer

A)  Mg, ether; CO2; then aqueous acid 
B)  NaCN; then aqueous acid 
C)  Both sets of reagents would work equally well. 
D)  Neither set of reagents would work well. 
A)  Mg, ether; CO2; then aqueous acid 
B)  NaCN; then aqueous acid 
C)  Both sets of reagents would work equally well. 
D)  Neither set of reagents would work well.

Question 20

Propose a synthesis of the transformation.

Accepted Answer

There are several possible synthetic rou

Exam 21: The Chemistry of Carboxylic Acid Derivatives

Predict the major organic product of the reaction. If you believe no reaction would occur, write NR.

A student is asked to monitor the reaction by infrared spectroscopy. Explain what peaks the student should use to monitor the reaction (appearance and disappearance).

Which reagents could be used to synthesize PhCOOH?

Given the synthetic sequence, predict the structures of the intermediate A and product B.

Predict the major organic product of the reaction. If you believe no reaction would occur, write NR.

The Ritter reaction is a useful method for producing substituted amides. Provide a detailed, arrow-pushing mechanism for the transformation. Show all reactive intermediates and all proton transfer steps. (It is not necessary to show every resonance structure for intermediates.)

Provide a detailed, arrow-pushing mechanism for the transformation. Show all reactive intermediates and all proton transfer steps. (It is not necessary to show every resonance structure for intermediates.)

Draw a triglyceride formed from glycerol and three molecules of stearic acid (CH3(CH2)16COOH).

Predict the major organic product of the reaction. If you believe no reaction would occur, write NR.

Predict the major organic product of the reaction. If you believe no reaction would occur, write NR.

Outline a synthesis for the transformation.

Describe the equilibrium constant for the reaction.

Draw a structure for these carboxylic acid derivatives. a. propyl 4-ethylbenzoate b. N-ethyl-N-methylpentanamide c. cyclohexanecarbonyl chloride

a. Provide arrow-pushing mechanisms for the reaction. Clearly show all intermediates. b. If you wanted to reverse the transformation, what reagent(s) would you use? No reaction mechanism is necessary.

Choose the best reagent(s) for carrying out the conversion.

Propose a synthesis of the transformation.

Chemical Bonding and Chemical Structure

Alkanes and Organic Nomenclature

The Curved-Arrow Notation, Resonance, Acids and Bases, and Chemical Equilibrium

Introduction to Alkenes and Alkynes

Addition Reactions of Alkenes and Alkynes

Principles of Stereochemistry

Cyclic Compounds and Reaction Stereochemistry

Nomenclature and Noncovalent Intermolecular Interactions

The Chemistry of Alkyl Halides

Free-Radical Reactions, Main-Group Organometallic Compounds, and Carbenes

The Chemistry of Alcohols and Thiols

The Chemistry of Ethers, Epoxides, Glycols, and Sulfides

Introduction to Spectroscopy

Nuclear Magnetic Resonance Spectroscopy

Dienes and Aromaticity

The Chemistry of Benzene and Its Derivatives

Allylic and Benzylic Reactivity

The Chemistry of Aryl Halides, Vinylic Halides, and Phenols

The Chemistry of Aldehydes and Ketones

The Chemistry of Carboxylic Acids

The Chemistry of Enolate Ions, Enols, and Α,β-Unsaturated Carbonyl Compounds

The Chemistry of Amines

Carbohydrates

The Chemistry of Thioesters, Phosphate Esters, and Phosphate Anhydrides

The Chemistry of the Aromatic Heterocycles and Nucleic Acids

Amino Acids, Peptides, and Proteins

Pericyclic Reactions

Filters

Draw a triglyceride formed from glycerol and three molecules of stearic acid (CH₃(CH₂)₁₆COOH).