Synthesis and structure of ansa-metallocene complexes (M=ZrCl2, TiCl2, YCl, and LuCl) containing the bis(2-methyl-4,5,6,7-tetrahydroinden-yl)dimethylsilane ligand

The three step synthesis of 2-methyl-4,5,6,7-tetrahydro-1H-indene from cyclohexyl methacrylate is described [(a) PPA cyclization; (b) LiAlH4 reduction; (c) HCl dehydration]. This annelated trisubstituted cyclopentadiene was bridged selectively to form ethylene- or dimethylsilyl-bridged bis(2-methyl-4,5,6,7-tetrahydro-1H-inden-1-yl) ligands. Metal complexes (M=ZrCl2, TiCl2, YCl, and LuCl) of the bis(2-methyl-4,5,6,7-tetrahydroinden-1-yl)dimethylsilane ligand were formed as meso/dl stereoisomeric mixtures in ratios from 1:1 to 2:1 dl:meso.