MONONUCLEAR SILYLVINYLIDENE RHODIUM COMPLEXES FROM SILYLALKYNES - THE SIME3 MIGRATION AS AN ALTERNATIVE TO THE [1,2]-H SHIFT

Vinylidene complexes can be prepared in the coordination sphere of rhodium with silylalkynes, RC = CSiMe3, whereas such complexes were hitherto accessible only with 1-alkynes, RC = CH. The synthesis proceeds via a [1,2]-SiMe3 migration along the alkyne C-C bond, which is just as facile as [1,2]-H shifts. The corresponding alkyne complexes formed as intermediates can also be isolated.