Resction mechanism Flashcards
Which of the following favors an SN2 mechanism?
Primary alkyl halide in polar aprotic solvent
What happens during the initiation step of free radical halogenation?
Cl₂ undergoes homolytic cleavage
Which of the following is a propagation step in halogenation of methane?
Both b and c
Termination in a radical chain reaction involves:
Radical recombination
Which halogen is most selective in radical halogenation?
Br₂
What is the mechanism for nitration of benzene?
Electrophilic aromatic substitution
What is the electrophile in nitration of benzene?
NO₂⁺
Friedel–Crafts alkylation uses:
RX and AlCl₃
What type of reaction occurs when benzene is treated with Br₂ and FeBr₃?
Electrophilic aromatic substitution
What is the function of AlCl₃ in Friedel–Crafts reactions?
Lewis acid catalyst
Which compounds undergo nucleophilic acyl substitution?
Carboxylic acid derivatives
What is the first step in acid-catalyzed ester hydrolysis?
Nucleophilic attack by water
What are the products of amide hydrolysis under acidic conditions?
Ammonium ion and carboxylic acid
What type of mechanism is Fischer esterification?
Nucleophilic acyl substitution
Why are acid chlorides more reactive than esters?
Cl⁻ is a better leaving group
What is the oxidation product of a primary alcohol with PCC?
Aldehyde
Oxidation of a secondary alcohol with KMnO₄ gives:
Ketone
Which reagent selectively reduces aldehydes and ketones?
NaBH₄
Which of the following is a common oxidizing agent?
CrO₃
What happens when a tertiary alcohol is oxidized?
No reaction
Which reaction mechanism involves the formation of a carbocation intermediate?
SN1
In an E2 elimination reaction, the base must abstract a proton from:
The β-carbon
Which of the following solvents would favor an SN1 reaction?
Water
Which of the following compounds undergoes a nucleophilic attack by a strong base in an E2 reaction?
2-Bromo-2-methylpropane
Which of the following can undergo a Friedel–Crafts acylation?
Benzene
Which of the following compounds undergoes nucleophilic substitution?
Methyl iodide
What type of bond is broken in an SN2 mechanism?
A C-LG bond
Which of the following is a hallmark of an E2 reaction?
A strong base abstracts a proton from the β-carbon
Which of the following is true of a carbocation intermediate?
It is highly unstable and prone to rearrangements
Which of the following will have the highest reactivity in an SN2 reaction?
Methyl chloride
What is the product of the reaction between an alkene and Br₂ in CCl₄?
Vicinal dibromide
What is the intermediate in a free radical halogenation of methane?
Methyl radical
What is the main difference between SN1 and SN2 reactions?
SN1 involves a carbocation intermediate; SN2 does not.
What is the major product of an alkene reaction with HBr in the presence of peroxide?
Anti-Markovnikov addition
Which of the following compounds will undergo an electrophilic addition reaction?
Alkene
Which of the following is true for the E1 mechanism?
The rate-determining step involves the departure of the leaving group
What is the result of a hydration reaction of an alkene?
Alcohol
Which of the following is the correct order of reactivity for electrophilic aromatic substitution?
Toluene > Benzene > Nitrobenzene
What is the most stable intermediate in an SN1 reaction?
Tertiary carbocation
Which of the following can result in the formation of a chiral center?
A reaction involving an alkene with a non-symmetrical substituent
Which of the following is a characteristic of the E2 mechanism?
The reaction occurs in a single step with a strong base
What is the key feature of the reaction between a halide and an alkene in an SN2 reaction?
Backside attack by the nucleophile
What does the E1 mechanism often result in?
Zaitsev’s product (most substituted alkene)
Which of the following reagents will not react with a primary alkyl halide in an SN2 mechanism?
Polar protic solvent
What is the product when a terminal alkyne is treated with HCl?
Markovnikov addition of Cl
Which of the following reactions produces a ketone?
Ozonolysis of an alkene
Which of the following reactions produces a carboxylic acid?
Oxidation of a primary alcohol with KMnO₄
What is the intermediate in the mechanism of nucleophilic substitution?
Tetrahedral transition state
In an E2 reaction, how should the hydrogen and leaving group be positioned?
Anti-periplanar
Which mechanism is favored by a strong, bulky base like t-BuOK?
E2
