Question

What organocuprate reagent would you use for the following substitutions?

Short answer

1. The organocuparate reagent used for the first reaction is

b. The organocuparate reagent used for the second reaction is

Step-by-step solution

Organocuprate Reagent.

Organocuprate reagent (RCuLi) is synthesized from organolithium reagent (RLi).

Organocuprate reagents are very useful for converting alkyl halide into alkanes, e.g.

1-bromobutane with organocuprate reagent (CH₃)₂ CuLi bromine is replaced by the methyl group and thus forms pentane, shown below:

Subpart (a) The reagent used for the given reaction.

In the product, four-carbon chain butane is coupled to the given reactant iodobenzene.

Here, the organocuprate reagent used is$\left({{\text{CH}}_{\text{3}}{\text{CH}}_{\text{2}}\underset{{\text{CH}}_{\text{3}}}{\underset{\text{|}}{{\text{CH}}_{\text{2}}}}}_{\text{2}}\right)\text{CuLi}$

Alkyl cuprate reagent

Subpart (b) The reagent used for the given reaction.

In the product, ethene is coupled to the given reactant 3-Bromo-2-butanone.

Here, the organocuprate reagent used is (CH₂=CH₂)₂CuLi .

Lithium divinylcuprate reagent