Organic Synthesis Quizzes for Year 12 Chemistry Students

Question 1

Utilizing retrosynthesis, determine the starting materials necessary to synthesize the target molecule, ibuprofen:

Target molecule: Ibuprofen

Accepted Answer

(B) Isobutylbenzene and 2-methylpropanoic acid

Answer

(A) Benzene and propanoic acid

Answer

(C) Toluene and butyric acid

Answer

(D) Phenol and isobutyl chloride

Question 2

Identify the reagent that is unsuitable for selectively oxidizing a primary alcohol to an aldehyde:

Accepted Answer

Potassium permanganate (KMnO4)

Answer

Pyridinium chlorochromate (PCC)

Answer

Sodium dichromate (Na2Cr2O7)

Question 3

Which step is NOT involved in retrosynthesis of an organic molecule?

Accepted Answer

Optimising the reaction conditions

Answer

Identifying the target molecule

Answer

Breaking down the target molecule into simpler starting materials

Answer

Evaluating alternative synthetic pathways

Question 4

Which step is NOT directly involved in retrosynthesis?

Accepted Answer

Optimizing the synthesis pathway for efficiency and yield

Answer

Identifying the target molecule

Answer

Breaking down the target molecule into simpler starting materials

Answer

Selecting and sequencing reactions to transform starting materials into the target molecule

Question 5

Which reagent can be employed to convert an alcohol into an alkyl halide via an SN2 reaction?

Accepted Answer

Hydrogen bromide

Answer

Sodium hydroxide

Answer

Potassium permanganate

Answer

Acetyl chloride

Question 6

In a nucleophilic substitution reaction, which species is the strongest nucleophile?

Accepted Answer

OH-

Answer

H2O

Answer

NH3

Answer

Cl-

Question 7

Retrosynthesis involves planning a synthetic pathway for a target molecule. Which step is NOT part of retrosynthesis?

Accepted Answer

Optimizing reaction conditions and sequence to improve synthesis efficiency and yield

Answer

Identifying functional groups and key structural features of the target molecule

Answer

Breaking down the target molecule into simpler starting materials

Answer

Selecting chemical reactions to transform starting materials into the target molecule

Question 8

Provide the correct IUPAC name for the following compound:

Accepted Answer

2-methyl-1-propene

Answer

1-methyl-2-propene

Answer

3-methyl-1-propene

Answer

2-methyl-2-propene

Question 9

In the laboratory synthesis of organic molecules, which technique is NOT directly involved?

Accepted Answer

Molecular modeling

Answer

Retrosynthesis

Answer

Protecting groups

Answer

Stereoselective reactions

Question 10

Which of the following is not a commonly used protecting group for alcohols?

Accepted Answer

Amide

Answer

Methyl ether

Answer

Trimethylsilyl ether

Answer

Acetate ester

Question 11

To convert an alcohol into an alkyl chloride, which reagent should be used?

Accepted Answer

Thionyl chloride

Answer

Sodium hydroxide

Answer

Potassium permanganate

Question 12

Determine the correct IUPAC name for the following compound: CH3CH(CH3)CH2CH2Br

Accepted Answer

2-Bromo-3-methylbutane

Answer

1-Bromo-3-methylbutane

Answer

2-Bromo-2-methylbutane

Question 13

What is the primary function of protecting groups in organic synthesis?

Accepted Answer

To prevent certain functional groups from participating in unwanted reactions

Answer

To increase the yield of the desired product

Answer

To accelerate reaction rates

Answer

To alter the regioselectivity of reactions

Question 14

Which of the following reactions exemplifies a nucleophilic substitution mechanism?

Accepted Answer

Reaction of an alcohol with an acyl chloride

Answer

Addition of HCl to an alkene

Answer

Elimination of water from an alcohol

Answer

Rearrangement of a carbocation

Question 15

What is the primary product of the reaction between an aldehyde and a primary amine?

Accepted Answer

A Schiff base

Answer

An imine

Answer

An enamine

Answer

An amide

Question 16

What is the hybridization of the carbon atoms in the C=C bond of an alkene?

Accepted Answer

sp2

Answer

sp

Answer

sp3

Answer

sp3d

Question 17

What is the correct IUPAC name for the compound CH3CH=CHCH2CH3?

Accepted Answer

2-Pentene

Answer

1-Pentene

Answer

3-Pentene

Answer

cis-2-Pentene

Question 18

Which technique is used to separate a mixture of organic compounds based on their boiling points?

Accepted Answer

Distillation

Answer

Chromatography

Answer

Crystallization

Answer

Extraction

Question 19

Which of the following is an essential step in the process of retrosynthesis?

Accepted Answer

Breaking down the desired molecule into simpler starting materials

Answer

Identifying the functional groups present in the desired molecule

Answer

Determining the necessary reaction conditions for the synthesis

Answer

Optimizing the yield of the reaction

Question 20

The Diels-Alder reaction involves the reaction of a conjugated diene with a:

Accepted Answer

Dienophile

Answer

Electrophile

Answer

Nucleophile

Answer

Free radical

Question 21

The Claisen condensation reaction is used to synthesize:

Accepted Answer

Esters

Answer

Amides

Answer

Ketones

Answer

Aldehydes

Question 22

Which reagent is used to convert an alcohol into an alkyl chloride via a substitution reaction?

Accepted Answer

SOCl₂

Answer

HCl

Answer

LiAlH₄

Answer

NaBH₄

Question 23

Which mechanism is involved in the formation of an amide bond between an amine and a carboxylic acid derivative?

Accepted Answer

Nucleophilic acyl substitution

Answer

SN1

Answer

SN2

Answer

Addition-elimination

Question 24

What is the primary purpose of using a Dean-Stark apparatus in organic synthesis?

Accepted Answer

To remove water from the reaction mixture

Answer

To maintain a constant temperature

Answer

To prevent air from entering the reaction

Answer

To stir the reaction mixture

Question 25

Which reaction exemplifies a Diels-Alder cycloaddition?

Accepted Answer

Cyclization of a diene

Answer

Addition of an alkene to a carbocation

Answer

Reaction of an aldehyde with a ketone

Answer

Elimination of HCl from an alkyl halide

Question 26

What is the product of the nucleophilic substitution reaction between 1-bromopropane and sodium cyanide?

Accepted Answer

Propionitrile

Answer

Propylamine

Answer

Propanoic acid

Answer

Propanol

Question 27

What is the main purpose of employing protecting groups in organic chemistry?

Accepted Answer

Preventing side reactions involving certain functional groups

Answer

Boosting the yield of the desired product

Answer

Activating functional groups for reactions

Answer

Purifying the final product

Question 28

Which reagent is suitable for carrying out a nucleophilic addition reaction on a ketone?

Accepted Answer

HCN

Answer

NH3

Answer

LiAlH4

Answer

PCC

Question 29

What is the hybridization of the carbonyl carbon in an aldehyde?

Accepted Answer

sp2

Answer

sp

Answer

sp3

Answer

sp3d

Question 30

Which of these is a common reducing agent used in organic reactions?

Accepted Answer

LiAlH4

Answer

KMnO4

Answer

HNO3

Answer

H2SO4

Question 31

What is the primary purpose of employing protecting groups in organic synthesis?

Accepted Answer

To shield certain functional groups from undesired reactions

Answer

To enhance the reactivity of specific functional groups

Answer

To isolate and purify the final product

Answer

To increase the overall yield of the reaction

Question 32

Which reaction is most suitable for synthesizing an alkene?

Accepted Answer

E2 elimination

Answer

Grignard reaction

Answer

Aldehyde reduction

Answer

Alkylation

Question 33

Which reagent is commonly used to convert an alcohol into an alkyl halide?

Accepted Answer

Hydrogen bromide

Answer

Sodium hydroxide

Answer

Potassium permanganate

Answer

Magnesium metal

Question 34

What is the IUPAC name for the compound CH3-CH=CH-COOH?

Accepted Answer

But-2-enoic acid

Answer

3-Butenoic acid

Answer

2-Butenoic acid

Answer

But-3-enoic acid

Question 35

Which of the following factors does not influence the rate of a chemical reaction?

Accepted Answer

Colour of the reaction mixture

Answer

Concentration of reactants

Answer

Temperature

Answer

Nature of the solvent

Question 36

What is the primary function of a Dean-Stark apparatus in organic reactions?

Accepted Answer

To eliminate water from the reaction mixture

Answer

To reflux the reaction mixture

Answer

To distill the product

Answer

To monitor the progress of the reaction

Question 37

In organic synthesis, what is the primary purpose of utilizing protecting groups?

Accepted Answer

To prevent undesired reactions at specific functional groups

Answer

To enhance the reaction yield

Answer

To improve the reaction's selectivity

Answer

To accelerate the reaction rate

Question 38

Which reagent is commonly employed for the nitration of an aromatic ring?

Accepted Answer

Sodium nitrite and sulfuric acid

Answer

Potassium permanganate

Answer

Hydrochloric acid

Answer

Sodium hydroxide

Question 39

In the context of retrosynthetic analysis, what constitutes the initial step?

Accepted Answer

Identifying the target molecule

Answer

Decomposing the target molecule into simpler starting materials

Answer

Determining the reaction pathway

Answer

Optimizing the synthesis strategy

Question 40

In electrophilic aromatic substitution reactions, which functional group demonstrates the highest reactivity?

Accepted Answer

Nitro group

Answer

Alkyl group

Answer

Aryl group

Answer

Carboxylic acid group

Question 41

After an SN2 reaction, what is the hybridization of the substituted carbon atom?

Accepted Answer

sp3

Answer

sp

Answer

sp2

Answer

sp3d

Question 42

Which of the following is not a commonly used protecting group for amino groups?

Accepted Answer

TBS

Answer

Boc

Answer

Fmoc

Answer

Acetyl

Question 43

The reaction of an alcohol with a carboxylic acid in the presence of an acid catalyst is known as:

Accepted Answer

Esterification

Answer

Neutralization

Answer

Saponification

Answer

Hydrolysis

Question 44

The mechanism of a nucleophilic substitution reaction proceeds via which steps?

Accepted Answer

Heterolytic bond cleavage followed by nucleophilic attack

Answer

Nucleophilic addition followed by proton transfer

Answer

Electrophilic addition followed by proton abstraction

Answer

Homolytic bond cleavage followed by radical recombination

Question 45

Select the definition that best describes the retrosynthesis approach to organic synthesis.

Accepted Answer

Working backward from the target molecule to identify possible synthetic routes

Answer

Working forward from the starting materials to identify the target molecule

Answer

Using a database of known reactions to find a path to the target molecule

Answer

Using computational methods to predict the most efficient synthetic route

Question 46

Which of the following is not a protecting group for an alcohol?

Accepted Answer

Ketone

Answer

Methyl ether

Answer

Acetate ester

Answer

Triethylsilyl ether

Question 47

Which of the following reagents is used for a nucleophilic substitution reaction of an alkyl halide?

Accepted Answer

KOH

Answer

LiAlH4

Answer

NaBH4

Answer

H2SO4

Question 48

The Diels-Alder reaction falls under which reaction category?

Accepted Answer

Cycloaddition reaction

Answer

Electrophilic aromatic substitution reaction

Answer

Nucleophilic addition reaction

Answer

Free radical reaction

Question 49

The concept of retrosynthesis is particularly useful in the context of:

Accepted Answer

Designing efficient synthetic pathways

Answer

Characterizing the structure of organic compounds

Answer

Predicting reaction mechanisms

Answer

Optimizing reaction conditions

Question 50

In retrosynthesis, the primary consideration is the:

Accepted Answer

Target molecule

Answer

Reactants

Answer

Reaction mechanism

Answer

Protecting group strategy

Question 51

Which of the following accurately describes the mechanism of an SN2 reaction involving an alkyl halide and an alkoxide?

Accepted Answer

Nucleophilic attack by the alkoxide on the alkyl halide

Answer

Electrophilic attack by the alkyl halide on the alkoxide

Answer

Radical attack by the alkoxide on the alkyl halide

Answer

Heterolytic cleavage of the alkyl halide by the alkoxide

Question 52

What is the primary purpose of utilizing a protecting group in organic synthesis?

Accepted Answer

Preventing undesired reactions at specific functional groups

Answer

Enhancing the reactivity of specific functional groups for subsequent reactions

Answer

Improving the solubility of a compound in a given solvent

Answer

Altering the boiling point of a compound

Question 53

In the reaction CH3CH2Br + NaOCH3, what is the expected product?

Accepted Answer

CH3CH2OCH3

Answer

CH3CH2OH

Answer

NaBr + CH3CH2OH

Answer

No reaction occurs

Question 54

Which of the following reagents is suitable for protecting an alcohol functional group?

Accepted Answer

Trityl chloride

Answer

Acetyl chloride

Answer

Sodium hydride

Answer

Lithium aluminum hydride

Question 55

In the reaction CH3CH=CH2 + HBr, what is the major product?

Accepted Answer

CH3CHBrCH3

Answer

CH2=CHCH2Br

Answer

CH3CH2CH2Br

Answer

No reaction occurs

Question 56

What is the major product formed in the reaction CH3CH2CH2Br + Mg?

Accepted Answer

CH3CH2CH2MgBr

Answer

CH3CH=CH2

Answer

CH3CH2CH3

Answer

No reaction occurs

Question 57

Which reagent is used to protect an alcohol as a tert-butyldimethylsilyl (TBDMS) ether?

Accepted Answer

tert-Butyldimethylsilyl chloride

Answer

Tetrahydrofuran

Answer

Triethylamine

Answer

Sodium borohydride

Question 58

What is the initial step in retrosynthesis?

Accepted Answer

Identifying the target molecule

Answer

Breaking down the target molecule into simpler starting materials

Answer

Identifying the necessary reagents and conditions

Answer

Carrying out the synthesis

Question 59

Which of the following is a nucleophilic substitution reaction?

Accepted Answer

SN2

Answer

E2

Answer

Diels-Alder

Answer

Pericyclic

Question 60

Which intermediate is formed during an SN2 reaction?

Accepted Answer

Transition state

Answer

Carbanion

Answer

Carbocation

Answer

Free radical

Question 61

Which reagent is used to oxidize primary alcohols to aldehydes?

Accepted Answer

Pyridinium chlorochromate

Answer

Potassium permanganate

Answer

Sodium borohydride

Answer

Lithium aluminium hydride

Question 62

Which of the following is a type of protecting group for an amine?

Accepted Answer

Carbamate

Answer

Acetal

Answer

Silyl ether

Answer

Ester

Question 63

What is the hybridization of the carbon atom in the carbonyl group of a ketone?

Accepted Answer

sp2

Answer

sp

Answer

sp3

Answer

sp3d

Question 64

Which step is NOT involved in planning a retrosynthesis of an organic molecule?

Accepted Answer

Optimizing the yield of the synthesis

Answer

Identifying the target molecule

Answer

Breaking down the target molecule into simpler starting materials

Answer

Using chemical reactions to connect the starting materials