The copper-catalyzed diboration of aldehydes was used in conjunction with the Matteson homologation, providing the efficient synthesis of β-hydroxyboronate esters. The oxygen-bound boronate ester was found to play a key role in mediating the homologation reaction, which was compared to the α-hydroxyboronate ester (isolated hydrolysis product). The synthetic utility of the diboration/homologation sequence was demonstrated through the oxidation of one product to provide a 1,2-diol.

A streamlined synthesis of β-hydroxy ketone substrates has been developed to further investigate a recently discovered cooperative Lewis base-mediated intramolecular carbonyl hydrosilylation reaction. The synthesis features an enone β-borylation/oxidation sequence that has proven to be quite general and high-yielding. This has allowed for additional investigations into the diastereoselectivity of the hydrosilylation reaction through the preparation of important polyketide fragments.

The synthetic utility of the method is demonstrated by the oxidation of one product to provide the protected diol (VI).

The hydroxy ketones (II), (X), and (XII), generated from enones by a convenient procedure, are found to undergo base‐mediated hydrosilylation with high diastereoselectivity.