31. Chelating Monoborane Phosphines: Rational and High-Yield Synthesis of [(Cod)Rh{(Eta(2)-BH3)Ph2PCH2PPh2}][PF6] (Cod=1,5-Cyclooctadiene)
Organometallics 2001, 20, 4434-4436
Ingleson, M.; Patmore, N. J.; Ruggiero, G. D.; Frost, C. G.; Mahon, M. F.; Willis, M. C.; Weller, A. S.
The rational and high-yield synthesis of [(COD)Rh{(eta (2)-BH3)Ph2PCH2PPh2}][PF6] (1), which bears a chelating monoborane phosphine, is reported; the solid-state structure shows that the borane coordinates to the metal via two 2e-3c B-H-Rh bonds, which in solution at room temperature are fluxional between all three B-H bonds. Complex 1 is isolated as an air-stable crystalline salt, and its applicability as a catalyst in organic synthesis has been demonstrated in the coupling of boronic acids with enones.