A New C2-Symmetric Ligand for ansa-Metallocene Chemistry: Synthesis and X-ray Crystal Structure of the ansa-Stannocene Complex rac-[(CHBut)2(C5H2But2)2]Sn

Reaction of the sterically demanding ligand precursor [(CHBut)2(C5H2But2)2]K2 with SnCl2 in THF gave the air-stable ansa-stannocene complex rac[(CHBut)2(C5H2But2)2]Sn. A single-crystal X-ray structure of the ansa-stannocene revealed a C2-symmetric and slipped bent structure, with the Sn2+ displaced toward an η2 bonding mode between bridged, highly tilted, and staggered 2,4-di-tert-butylcyclopentadienyl rings.