Double Phosphinoboration of CO₂: A Facile Route to Diphospha‐Ureas

Abstract

Abstract The reactions of CO 2 with a series of phosphinoboranes, including R 2 PBpin (R=Ph, t Bu; pin=pinacol), R 2 PBMes 2 (R=Ph, t Bu; Mes=2,4,6‐Me 3 ‐C 6 H 2 ), and R 2 PBcat (R=Ph, t Bu, Mes; cat=catechol) are described. Although R 2 PBpin and R 2 PBMes 2 afford products of the form R 2 PCO 2 Bpin (R=Ph 1 , t Bu 4 ) and R 2 PCO 2 BMes 2 (R=Ph 2 , t Bu 3 ), respectively, R 2 PBcat lead to further reaction affording the diphospha‐ureas, (R 2 P) 2 CO (R=Ph 5 , t Bu 6 , Mes 7 ), together with O(Bcat) 2 . Computational studies provide insight into the mechanism, revealing an intermediate derived from double phosphinoboration of CO 2 .