Synthesis and Reactions of π‑Conjugated Iminoboranes Stabilized by Intramolecular Imine Groups

Reduction of the boron difluorides HC­[(CBut)­(NAr)]2BF2 led to C–N bond cleavage to give the iminoborane [C­(But)­CHC­(But)­NAr]­BNAr (2, Ar = 2,6-Me2C6H3; 2′, Ar = 2,6-Pri2C6H3) stabilized by an intramolecular imine group. Reaction of 2 with NHC resulted in nucleophilic attack on the α-carbon atom to give [C­(But)­(NHC)­CHC­(But)­NAr]­BNAr (3). 2 reacted with CO2 to give [C­(But)­CHC­(But)­NAr]­B­(CO2)­NAr (4).