Aldehydes & Ketones - Synthesis I

For each of the conversions shown on the left, provide the reactants and reagents necessary to convert the starting material into the final product. Pay particular attention to the regiochemistry and stereochemistry of the reactions you utilize.
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In order to prepare 3-methylcyclohexanone from 2-cyclohexenone, a methyl group must be introduced into the b-carbon of the a-b-unsaturated ketone. The conjugate addition of an alkyl group is most readily accomplished using a dialkylcopper lithium reagent.

The target molecule is simply the oxime of 2-cyclohexenone. Oximes can be prepared from the parent ketone or aldehyde by reaction with NH₂OH.

In order to prepare cyclohexene from 2-cyclohexenone, the carbonyl group must be reduced to the hydrocarbon, without reducing the double bond. This is readily accomplished using the Wolff-Kishner reduction (H₂NNH₂ in the presence of KOH); the Clemmensen reduction will also work (Zn(Hg)/H₃O⁺).

In order to prepare 3-phenylcyclohexanone from 2-cyclohexenone, a phenyl group must be introduced into the b-carbon of the a-b-unsaturated ketone. The conjugate addition of an aryl group is most readily accomplished using a diarylcopper lithium reagent.

In the target molecule, a methyl group has been introduced into the b-carbon of the a-b-unsaturated ketone. The conjugate addition of an alkyl group is most readily accomplished using a dialkylcopper lithium reagent.

The target molecule is simply the oxime of 2-cyclohexenone. Oximes can be prepared from the parent ketone or aldehyde by reaction with NH₂OH.

In the target molecule, the carbonyl group has been reduced to the hydrocarbon, without reducing the double bond. This is readily accomplished using the Wolff-Kishner reduction (H₂NN H₂ in the presence of KOH); the Clemmensen reduction will also work (Zn(Hg)/H₃O⁺).

In the target molecule, a phenyl group has been introduced into the b-carbon of the a-b-unsaturated ketone. The conjugate addition of an aryl group is most readily accomplished using a diarylcopper lithium reagent.