Phosphine catalyzed reduction of CO_2 with boranes

摘要

Phosphine is shown to catalyse the reaction of CO_2 with 9-BBN to give mixtures of HCO_2(B(C_8H_(14)))3 H_2C(OB(C_8H_(14)))_2 4 and MeOB(C_8H_(14)) 5; at 0.02 mol% of tBu_3P 5 is obtained in 98% yield at 60℃ with TON of almost 5500 and a TOF of 170. Under stoichiometric conditions the species (R_3PCH_2O)(HC(O)O)B(C_8H_(14)) (R = tBu 1,4-MeC_6H_4 2) were isolated and characterized.