Question

In addition to organic halides, alkyl tosylates (R'OTs, Section 9.13) also react with organocuprates ( ${\mathbf{R}}_{\mathbf{2}}\mathbf{CuLi}$) to form coupling products R-R'. When 2° alkyl tosylates are used as starting materials ( ${\mathbf{R}}_{\mathbf{2}}\mathbf{CHOTs}$), inversion of the configuration at a stereogenic center results. Keeping this in mind, draw the product formed when each compound is treated with ${\mathbf{\left(}{\mathbf{CH}}_{\mathbf{3}}\mathbf{\right)}}_{\mathbf{2}}\mathbf{CuLi}$.

a.

b.

Short answer

Answer

a.

b.

Step-by-step solution

Alkyl tosylates

The incorporation of tosyl chloride into alkyl alcohols leads to the formation of alkyl tosylates. Tosyl groups serve as protecting groups in the area of organic chemistry.

Reaction of alkyl tosylates with organocuprate reagents

The combination of alkyl tosylate with an organocuprate reagent results in the generation of a product possessing new C-C bonds.

Starting material needed to synthesize the given compounds

The species comprising copper-carbon bonds are termed organocuprate reagents. These reagents function as nucleophiles and combine with alkyl tosylate to form coupling products and comprise a new C-C bond.

a. The reaction of compound a with organocuprates can be given as follows.

Reaction of compound a with organocuprates

b. The reaction of compound b with organocuprates can be given as follows.

Reaction of compound b with organocuprates