Homologation Tactics with Diborylmethane via α ‐Boryl Carbanions

Abstract

The potential applications of diborylmethane as an essential tool for homologative synthetic protocols are described in this chapter. The activation of diborylmethane with transition-metal complexes or alkoxy salts from the main group metals allows the generation of suitable α-boryl and α-diboryl carbanions that perform interesting electrophilic trapping strategies. Borylmethide palladium salts and borylmethide copper salts are the most effective to homologate alkyl, allyl, and aryl electrophiles. Since diborylmethane can be deborylated or deprotonated with Li + , Na + , and K + salts, the resulting α-boryl and α-diboryl carbanions can be directly used with alkyl, aryl, and allyl electrophiles; carbonyls, and epoxides/aziridines for homologative purposes. However, the borylmethide silver salts and the diborylmethide zinc salts have been used principally to transmetalate with Ir, Pd, or Cu complexes, to guarantee their implication in alternative catalytic process.