Final: True and False

Question 1

The kinetic product is always more stable than the thermodynamic product

Answer 1

False

Question 2

The Dieckmann condensation is an intramolecular Claisen condensation that forms cyclic β-keto esters

Answer 2

True

Question 3

Electrophilic aromatic substitution reactions proceed through a carbocation intermediate

Answer 3

True

Question 4

Hydrogen bonding in alcohols is stronger than in ethers due to the presence of an -OH group

Answer 4

True

Question 5

Hydrolysis of esters in a basic medium forms carboxylic acid and an alcohol

Answer 5

False

Question 6

DMSO is a common solvent for SN2 reactions because it is polar aprotic

Answer 6

True

Question 7

The rate-determining step in a reaction always has the highest energy transition state

Answer 7

True

Question 8

1,3,5-Hexatriene is aromatic

Answer 8

False

Question 9

Pyrimidine is less basic than pyridine due to the presence of electron-withdrawing nitrogen atoms

Answer 9

True

Question 10

The kinetic product of a reaction forms faster but is less stable than the thermodynamic product

Answer 10

True

Question 11

Base-catalyzed hydrolysis of esters proceeds via a tetrahedral intermediate

Answer 11

True

Question 12

The driving force for the decarboxylation of malonic acid is the loss of CO₂ and formation of a stable resonance structure

Answer 12

True

Question 13

Tautomerization between keto and enol forms always requires a catalytic acid or base

Answer 13

False

Question 14

The restricted rotation of the C-N bond in amides is due to resonance

Answer 14

True

Question 15

Carboxylic acids can undergo alkylation via the use of alkyl bromides under basic conditions

Answer 15

False

Question 16

Sodium borohydride (NaBH₄) selectively reduces aldehydes and ketones but not esters or carboxylic acids

Answer 16

True

Question 17

Claisen condensation reactions are irreversible under acidic conditions

Answer 17

False

Question 18

Wittig reactions can be used to selectively form Z- or E-alkenes depending on the type of phosphonium ylide

Answer 18

True

Question 19

Reduction of cyclopentanone with LiAlH₄ gives a racemic mixture of alcohols

Answer 19

True

Question 20

Aldehydes are easily oxidized in water due to hydration into geminal diols

Answer 20

True

Question 21

Epoxides are highly reactive because of the high ring strain in their three-membered ring

Answer 21

True

Question 22

Ester carbonyl groups can be protected as acetals using diols in acidic conditions

Answer 22

False

Question 23

Conjugation stabilizes allyl cation intermediates, making reactions involving them faster

Answer 23

True

Question 24

The formation of imines from aldehydes or ketones requires the removal of water to drive the reaction to completion

Answer 24

True

Question 25

Conjugated dienes are more stable than isolated dienes due to delocalization of π-electrons

Answer 25

True

Question 26

In the Diels-Alder reaction, the diene must be in an s-trans conformation for the reaction to occur

Answer 26

False

Question 27

Electrophilic aromatic substitution reactions are faster on benzene than on toluene

Answer 27

False

Question 28

Halogens are deactivating groups in electrophilic aromatic substitution but are ortho/para-directing

Answer 28

True

Question 29

Polycyclic aromatic hydrocarbons like naphthalene follow Hückel’s rule

Answer 29

True

Question 30

Aldehydes are generally more reactive than ketones in nucleophilic addition reactions

Answer 30

True

Question 31

The reaction of an aldehyde with a primary amine forms an imine

Answer 31

True

Question 32

Ketones react with diols to form cyclic acetals

Answer 32

True

Question 33

Carboxylic acids are reduced to primary alcohols using sodium borohydride (NaBH₄)

Answer 33

False

Question 34

Acid chlorides react with alcohols to form esters

Answer 34

True

Question 35

Enolates are resonance-stabilized intermediates formed when α-hydrogens are deprotonated

Answer 35

True

Question 36

The kinetic enolate is formed faster than the thermodynamic enolate and is favored at low temperature

Answer 36

True

Question 37

In a mixed aldol reaction, using one compound without α-hydrogens can help control product formation

Answer 37

True

Question 38

The enolate ion can act as both a nucleophile and a base

Answer 38

True

Question 39

The Claisen condensation requires at least one reactant to have two α-hydrogens

Answer 39

True

Question 40

Epoxides react with nucleophiles under acidic conditions to open the ring at the more substituted carbon

Answer 40

True

Question 41

Under basic conditions, epoxides open at the less substituted carbon due to SN2-like mechanism

Answer 41

True

Question 42

The formation of an epoxide from an alkene requires a peracid such as mCPBA

Answer 42

True

Question 43

Epoxides are more reactive than ethers because of the ring strain in the three-membered ring

Answer 43

True

Question 44

Epoxide opening with a Grignard reagent results in the formation of a secondary alcohol

Answer 44

False

Question 45

All reactions that have competing reaction pathways and transition states will always give the thermodynamically more stable product

Answer 45

False

Question 46

Cyclopropanone is an aromatic compound

Answer 46

False

Question 47

Claisen condensation of methyl acetate in the presence of sodium methoxide, followed by neutralization with acid, gives methyl acetoacetate CH3COCH 2CO 2CH 3.

Answer 47

True

Question 48

Electrophilic aromatic substitution at high temperatures (> 50° C) is a concerted process, at lower temperatures (< 0° C) it’s a multi-step reaction with intermediates

Answer 48

False

Question 49

Hydrogen bonding helps contribute to water’s high boiling point of 100° C

Answer 49

True

Question 50

Hydrolysis of amides and esters can be catalyzed by acid or by base

Answer 50

True

Question 51

THF is a good solvent for organometallic reagents because it’s aprotic and its lone pair of electrons can coordinate to the metal in the organometallic bond

Answer 51

True

Question 52

The fastest step in a multistep reaction is called the rate-determining step

Answer 52

False

Question 53

1,3-cyclobutadiene is aromatic

Answer 53

False

Question 54

Pyridine is more basic than pyrrole

Answer 54

True

Question 55

The kinetic product of reaction of 1,3-butadiene with HBr is 1-bromo-2-trans-butene

Answer 55

False

Question 56

Acid-catalyzed hydrolysis of nitriles proceeds via initial formation of a primary amide, followed by further hydrolysis to a carboxylic acid

Answer 56

True

Question 57

The driving force for decarboxylation of beta-keto acids is the loss of CO2 gas and formation of an enol

Answer 57

True

Question 58

Phenol does not have a keto tautomer

Answer 58

False

Question 59

Rotation about the C-N sigma bond in an amide is faster than rotation about the C-Cl sigma bond in an acid chloride, since Cl is such a big atom

Answer 59

False

Question 60

Carboxylate anions cannot be alkylated with alkyl bromides

Answer 60

False

Question 61

Sodium borohydride will reduce the C=O bond in ketones, esters and amides

Answer 61

False

Question 62

Aldol condensation reactions are reversible

Answer 62

True

Question 63

Usually, there are 2 different ways to prepare an internal alkene via the Wittig reaction

Answer 63

True

Question 64

Reduction of 2-methylcyclobutanone with LiAlH 4 gives a pair of diastereomers

Answer 64

True

Question 65

Oxidation of an aldehyde group never occurs in water, because the carbonyl group is protected as its 1,1-geminal diol

Answer 65

False

Question 66

Epoxides are reactive due to ring strain and torsional strain

Answer 66

True

Question 67

Just like ketones, ester carbonyls can be easily “protected” with 1,2-diols

Answer 67

False

Question 68

Conjugation in allyl radical intermediate makes it easier to break C-H σ Bond

Answer 68

True