Syntheses and Structures of Terminal Arylalumylene Complexes

Terminal arylalumylene complexes of platinum [Ar-Al-Pt(PCy3 )2 ] (Ar=2,6-[CH(SiMe3 )2 ]2 C6 H3 (Bbp) or 2,6-[CH(SiMe3 )2 ]2 -4-(tBu)C6 H2 (Tbb)) have been synthesized either by the reaction of a dialumene-benzene adduct with [Pt(PCy3 )2 ], or by the reduction of 1,2-dibromodialumanes Ar(Br)Al-Al(Br)Ar in the presence of [Pt(PCy3 )2 ]. X-Ray crystallographic analysis reveals that the AlPt bond lengths of these arylalumylene complexes are shorter than the previously reported shortest AlPt distance. DFT calculations suggest that the AlPt bonds in the arylalumylene complexes have a significantly high electrostatic character.