Boron-Promoted Deprotonative Conjugate Addition: Geminal Diborons as Soft Pronucleophiles and Acyl Anion Equivalents.

Conjugate addition of α-boron-stabilized carbanions is an underexplored reaction modality. Existing methods require deborylation of geminal di-/triboryl alkanes and/or the presence of additional activating groups. We report the 1,4-addition of α,α-diboryl carbanions generated via deprotonation of the corresponding geminal diborons.