Suggest a combination of organic halide and cuprate reagent appropriate for the preparatio...

Suggest a combination of organic halide and cuprate reagent appropriate for the preparation of each of the following compounds:

(a) 2-Methylbutane

(b) 1,3,3-Trimethylcyclopentene

Sample Solution (a) First inspect the target molecule to see which are the best bonds to form by reaction of an alkyl halide and a cuprate, bearing in mind that neither the alkyl halide nor the alkyl group of the lithium dialkylcuprate should be secondary or tertiary.

There are two combinations, both acceptable, that give the H3C—CH2 bond: