Modular Synthesis of Geminal Triarylmethyl and Chiral Diarylmethyl Boronates via Arylation of Solid α-Boryl Organozinc Reagents.

Geminal multiarylmethyl moieties are crucial structural components in a wide variety of bioactive and pharmaceutical compounds. Herein, we present a Pd-catalyzed enantioconvergent arylation of racemic stable solid benzylic α-boryl organozinc reagents, enabling the synthesis of chiral gem-diarylmethyl boronates. In addition, the previously unexplored sterically hindered gem-triarylmethyl boronates were readily accessed via successive dual arylation of benzylboronates. The synthetic practicability of gem-triarylmethyl boronates was demonstrated by their conversion to triaryl methanol, triaryl alkane, and tetraarylmethane derivatives.