How might conjugate addition reactions of lithium diorganocopper reagents be used to synthesize the following compounds?

To choose the reactant to form the conjugate addition product steps which follow are as follows:

• Aldehyde and ketone carbon numbered “1” and counted two carbons away from the carbonyl carbon. The double bond in the alpha, beta-unsaturated starting material is made by connecting the carbon numbers “2’’ and “3” by a double bond.
• The group bonded to the “3” carbon formed the alkyl lithium reagent.

2-heptanone is synthesized by reacting with the following reagent:

• but-3-en-2-one comes from forming a double bond between 2^nd and 3^rd carbon.
• Alkyl lithium reagent $\text{Li}{\left({\text{CH}}_{\text{3}}{\text{CH}}_{\text{2}}{\text{CH}}_{\text{2}}\right)}_{\text{2}}\text{Cu}$ comes from the group joining the 3^rd carbon.

Thus but-3-en-2-one reacting with $\text{Li}{\left({\text{CH}}_{\text{3}}{\text{CH}}_{\text{2}}{\text{CH}}_{\text{2}}\right)}_{\text{2}}\text{Cu}$followed by acidic workup results in the synthesis of 2-heptanone.

Synthesis of 2-heptanone

3,3-dimethylcyclohexanoneis synthesized by reacting with the following reagent:

• 3-methylcyclohex-2-enone comes from forming a double bond between 2^nd and 3^rd carbon.
• Alkyl lithium reagent $\text{Li}{\left({\text{CH}}_{\text{3}}\right)}_{\text{2}}\text{Cu}$ comes from the group joining the 3^rd carbon.

Thus reacting 3-methylcyclohex-2-enone with $\text{Li}{\left({\text{CH}}_{\text{3}}\right)}_{\text{2}}\text{Cu}$followed by acidic workup results in the synthesis of 3,3-dimethylcyclohexanone.

Synthesis of 3,3-dimethylcyclohexanone

4-tert-Butyl-3-ethylcyclohexanone is synthesized by reacting with the following reagent:

• 4-tert-Butyl-cyclohex- 2-enone comes from forming a double bond between 2^nd and 3^rd carbon.
• Alkyl lithium reagent $\text{Li}{\left({\text{CH}}_{\text{3}}{\text{CH}}_{\text{2}}\right)}_{\text{2}}\text{Cu}$comes from the group joining the 3^rd carbon.

Thus reacting with 4-tert-Butyl-cyclohex- 2-enone$\text{Li}{\left({\text{CH}}_{\text{3}}{\text{CH}}_{\text{2}}\right)}_{\text{2}}\text{Cu}$ followed by acidic workup synthesizes 4-tert-Butyl-3-ethylcyclohexanone.

Synthesis of 4-tert-Butyl-3-ethylcyclohexanone

8a-vinyloctahydronaphthalenis synthesized by reacting with the following reagent:

• 4,4a,5,6,7,8-hexahydronaphthalen-2(3H)-one comes from forming a double bond between 2^nd and 3^rd carbon.
• Alkyl lithium reagent$\text{Li}{\left({\text{CH}}_2\text{=CH}\right)}_{\text{2}}\text{Cu}$ comes from the group joining the 3^rd carbon.

Thus reacting,4a,5,6,7,8-hexahydronaphthalen-2(3H)-one with$\text{Li}{\left({\text{CH}}_2\text{=CH}\right)}_{\text{2}}\text{Cu}$ followed by acidic workup synthesizes 8a-vinyloctahydronaphthalen.

Synthes of 8a-vinyloctahydronaphthalen