Bisphosphine monoxide (BPMO) complexes of transition metals have gained increasing interest as catalyst in organic synthesis. There are various strategies to prepare BPMO metal complexes. In our previous studies, the gold(I) complex [Au(dppbzO)Cl] (dppbz = 1,2-bis(diphenylphosphino)benzene) was discovered in an unexpected reaction with dppbz and Na[AuCl4] nH2O involving the reduction of the gold(III) center in acetonitrile and in the presence of water. In analogy to this one-pot synthesis, a rhodium(I) BPMO complex was attempted to prepare by reaction between dppbz and RhCl3 nH2O. However, this reaction resulted in the formation of fac-[RhCl3(dppbz)(CH3CN)]. When changing the reaction conditions, in THF and in the presence of PPh3, mer-[RhCl3(dppbzO)(thf)] was formed. The formation of the rhodium(III) bisphosphine monoxide complex involves presumably oxygen transfer mediated by PPh3. Extended NMR and MS studies where performed to elucidate the reaction mechanism.

Synthesis of new bisphosphine and bisphosphine monoxide rhodium(III) complexes: Expected and unexpected results

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.