One-carbon homologation of unsymmetrical ketones through magnesium β-oxido carbenoid rearrangement and trapping the enolate intermediates with electrophiles
A procedure for one-carbon homologation of unsymmetrical ketones, including one-carbon ring-expansion of 2-substituted cyclohexanones, through magnesium β-oxido carbenoid rearrangement as the key reaction is described. Addition of the α-sulfinyl carbanion of 1- chloroethyl p-tolyl sulfoxide to an unsymmetrical ketone gave two diastereomers as adducts in good yields. The adducts were treated with a base to give alkoxides, which were treated ...
