Aza-Matteson Reactions via Controlled Mono- and Double-Methylene Insertions into Nitrogen-Boron Bonds

Boron-homologation reactions represent an efficient and programmable approach to prepare alkylboronates, which are valuable and versatile synthetic intermediates. The typical boron-homologation reaction, also known as the Matteson reaction, involves formal carbenoid insertions into C-B bonds. Here we report the development of aza-Matteson reactions via carbenoid insertions into the N-B bonds of aminoboranes. By changing the leaving groups of the carbenoids and altering Lewis acid activators, selective mono- and double-methylene insertions can be realized to access various alpha- and beta-boron-substituted tertiary amines, respectively, from common secondary amines. The derivatization of complex amine-containing bioactive molecules, diverse functionalization of the boronate products, and sequential insertions of different carbenoids have also been achieved.

Automated summary

Boron-homologation reactions offer an efficient and programmable method for the synthesis of alkylboronates, providing valuable and versatile synthetic intermediates. By implementing aza-Matteson reactions, selective mono- and double-methylene insertions can be achieved, allowing access to various alpha- and beta-boron-substituted tertiary amines. Additionally, derivatization of complex amine-containing bioactive molecules, diverse functionalization of boronate products, and sequential insertions of different carbenoids have all been successfully demonstrated.