A magnetic spin transfer NMR study of tertiary phosphine exchange in rhodium(I) complexes

Magnetic spin transfer NMR was used to investigate phosphine exchange reactions in complexes of the type [Rh(N,O-Bid)(CO)(PPh3)]. The rate of exchange in [Rh(2,6-Cl2-Phony)(CO)(PPh3)] is approximately three times faster than the methylated counterpart; the methyl substituents increase the electron density of the d-orbitals of the rhodium atom and stabilize the intermediate.156