Stereoselective Direct Chlorination of Alkenyl MIDA Boronates: Divergent Synthesis of E and Z α-Chloroalkenyl Boronates

Abstract

The individual molecules of α-chloroalkenyl boronates include both an electrophilic C-Cl bond and a nucleophilic C-B bond, which makes them intriguing organic synthons. Reported herein is a stereodivergent synthesis of both E and Z α-chloroalkenyl N-methyliminodiacetyl (MIDA) boronates through the direct chlorination of alkenyl MIDA boronates using tBuOCl and PhSeCl reagents, respectively. Both reaction processes are stereospecific and the use of sp³ -B MIDA boronate is the key contributor to the reactivity. The synthetic value of the boronate products was also demonstrated.

Keywords: alkenyl boronates; chlorination; divergent synthesis; iterative coupling; stereoselective synthesis.