Facile insertion of a cyclic alkyl(amino) carbene carbon into the B-B bond of diboron(4) reagents

We report herein the room temperature insertion of the carbene carbon atom of the cyclic (alkyl)(amino) carbene cAAC Me into the B-B single bonds of the diboron(4) compounds B 2 pin 2 , B 2 cat 2 , B 2 neop 2 , and B 2 eg 2 (pin = pinacolato, cat = catecholato, neop = neopentylglycolato, eg = ethyleneglycolato). The carbene cAAC Me reacts with diboron compounds via an irreversible insertion into the B-B bond.