On the scope of the Pt-catalyzed Srebnik diborylation of diazoalkanes. An efficient approach to chiral tertiary boronic esters and alcohols via B-stabilized carbanions

Conditions milder than those previously reported are shown to be generally applicable to the Pt-catalyzed insertion of non-carbonyl-stabilized diazoalkanes into B2pin2. Selective transformation of one (pinacolato)boryl unit in the products is enabled by rapid, low-temperature deboronation in the presence of a Lewis base and genesis of a highly reactive B-stabilized carbanion.