Double N,B-Type Bidentate Boryl Ligands Enabling a Highly Active Iridium Catalyst for C–H Borylation

Boryl
ligands hold promise in catalysis due to their very high
electron-donating property. In this communication double N,B-type
boryl anions were designed as bidentate ligands to promote an sp2 C–H borylation reaction. A symmetric pyridine-containing
tetraamino­diborane(4) compound (1) was readily
prepared as the ligand precursor that could be used, in combination
with [Ir­(OMe)­(COD)]2, to in situ generate
a highly active catalyst for a broad range of (hetero)­arene substrates
including highly electron-rich and/or sterically hindered ones. This
work provides the first example of a bidentate boryl ligand in supporting
homogeneous organometallic catalysis.