Synthesis of a Heterobimetallic Rhodium−Iron Complex Containing an η3-Interaction between Rhodium and the B−Cipso−Cortho Unit of a Triarylborane

Reaction of [{RhCl(CO)2}2] with a phosphine/thioether/borane ligand (TXPB) gave [Rh(μ-Cl)(CO)(TXPB)] (1), a rare example of a complex containing a M−Cl−BR3 bridging interaction. Reaction of 1 with K[CpFe(CO)2] gave [(TXPB)Rh(μ-CO)2Fe(CO)Cp] (2), which contains an unprecedented η3-interaction between rhodium and the B−Cipso−Cortho unit of a triarylborane. DFT calculations suggest a bonding description intermediate between that expected for an isolated borane/alkene complex and a fully delocalized allyl-like complex.