Carbonyl a-Substitution Reactions - Set #I
For each of the reactions on the left, predict the major organic product. Pay particular attention to the regiochemistry and stereochemistry of the reaction.Click the mouse on the reactant molecule to view the answer;
click on the reagent to briefly review the reaction.
LDA (lithium diisopropylamide) is a very strong base and will completely convert a carbonyl compound into the corresponding enolate anion. Reaction of this complex with an alkyl halide results in the alkylation of the carbonyl compound at the a-position.
Acetic acid will catalyze the enolization of aldehydes and ketones; when this enol reverts back to the carbonyl compound, the anion which is formed on the a-carbon can be trapped by reaction with Br2 to give the a-bromo carbonyl compound.
LDA (lithium diisopropylamide) is a very strong base and will completely convert a carbonyl compound into the corresponding enolate anion. Reaction of this complex with an alkyl halide results in the alkylation of the carbonyl compound at the a-position.
I2 in aqueous base will undergo sequential addition of iodine at the alpha carbon of a methyl ketone (or on the methyl group of acetaldehyde) to give a triiodo derivative. This will decompose in the presence of base to give iodoform (CHI3) and the corresponding carboxylic acid.
LDA (lithium diisopropylamide) is a very strong base and will completely convert a carbonyl compound into the corresponding enolate anion. Reaction of this complex with an alkyl halide results in the alkylation of the carbonyl compound at the a-position.
Acetic acid will catalyze the enolization of aldehydes and ketones; when this enol reverts back to the carbonyl compound, the anion which is formed on the a-carbon can be trapped by reaction with Br2 to give the a-bromo carbonyl compound.
LDA (lithium diisopropylamide) is a very strong base and will completely convert a carbonyl compound into the corresponding enolate anion. Reaction of this complex with an alkyl halide results in the alkylation of the carbonyl compound at the a-position.
I2 in aqueous base will undergo sequential addition of iodine at the alpha carbon of a methyl ketone (or on the methyl group of acetaldehyde) to give a triiodo derivative. This will decompose in the presence of base to give iodoform (CHI3) and the corresponding carboxylic acid.
