σ-Accepting properties of a chlorobismuthine ligand.

BiZness as usual? Not exactly! The bismuth atom of the tridentate diphosphinobismuthine (o-(Ph(2)P)C(6)H(4))(2) BiCl behaves as a Z rather than L ligand when in the coordination sphere of late transition metals such as gold. The σ-acceptor behavior of Bi is supported by its disphenoid coordination geometry and theoretical studies, which show a Au→Bi interaction.