||A Highly Active PBP-Iridium Catalyst for the Dehydrogenation of Dimethylamine-Borane: Catalytic Performance and Mechanism
Kwan, Enrique Huang ,
Ogawa, HayatoYamashita, Makoto
2462 , 2017-07-07 , Wiley
A long-tethered boron-containing (P-B-P) pincer ligand with an aliphatic backbone was synthesized. Oxidative addition of the B−H bond in the ligand to [Ir(coe)2Cl]2 (coe=cyclooctene) afforded the (P-B-P)Ir(H)Cl complex. A catalyst system comprising the iridium complex and KOtBu showed excellent performance in the dehydrocoupling of N,N-dimethylamine–borane (DMAB), releasing 1 equivalent of dihydrogen gas from a concentrated solution of DMAB at a low catalyst loading of 0.05 mol % and with an initial turnover frequency of approximately 3400h^−1. The dihydride (P-B-P)Ir(H)2 complex also catalyzed the dehydrogenation of DMAB and was postulated as one of the intermediates in the catalytic cycle.