Flexible Platinum(0) Coordination to a Ditungsten Ethanediylidyne

Abstract

The lithiocarbyne [W(≡CLi)(CO)₂ (Tp*)] (Tp*=hydrotris(3,5-dimethylpyrazol-1-yl)borate) reacts with [PtCl₂ (L₂ )] (L₂ =1,5-cyclo-octadiene, norbornadiene) to furnish ditungsten ethanediylidyne complexes, [W₂ {μ-C₂ Pt(L₂ )}(CO)₄ (Tp*)₂ ], wherein a trigonal platinum(0) center unsymmetrically ligates one W≡C bond in the solid state but rapidly shimmies between the two W≡C bonds in solution. The η⁴ -dienes are displaced by monodentate CO or isocyanide ligands to provide derivatives where both W≡C bonds coordinate to a single Pt⁰ center, attended by significant distortion of the WCCW spine.

Keywords: bis(carbyne)s; carbido ligands; carbynes; dicarbido ligands; polymetallic compounds.