Structural Elucidation of the Illustrious Tebbe Reagent

The Tebbe reagent, [Cp2Ti­(μ2-Cl)­(μ2-CH2)­AlMe2] (1), has finally been structurally characterized due to the fortuitous formation of cocrystals of 1 and [Cp2Ti­(μ2-Cl)2AlMe2] (2). Single crystals of 1 and 2, despite being extremely reactive and forming an amorphous white coat, can be mounted and data collected to high resolution, thereby providing for the first time a solid-state representation of a titanium methylidene adduct with diphilic AlClMe2.