Substituted ring-fused yttrium derivatives - X-ray crystal structures of [(L'YCl2.THF)(2)LiCl.2THF] and [{L'YCl(OH)}(6).2THF] (L'=2-phenyl-4,5,6,7,8-hexahydroazulenyl)

The reaction of lithium salts of ring-fused ligands (L), where the ring fused to the cyclopentadienyl moiety is a saturated one (six, seven, or eight carbon atoms), with YCl3 in THF in 2:1 and 1:1 molar ratios affords complexes of formula [L2YCl](2) and [(LYCl2 center dot THF)(2)LiCl center dot 2THF], respectively. Here we report the synthesis, spectroscopic characterization, and X-ray crystal structure of [(L'YCl2 center dot THF)(2)LiCl center dot 2THF] (L' = 2-phenyl-4,5,6,7,8-hexahydroazulenyl), together with the crystal structure of the hexameric species [{L'YCl(OH)}(6)center dot 2THF], which was quite unexpectedly isolated during the attempted crystallization of the latter complex and is probably formed by partial hydrolysis of that complex. The activity of the new complexes towards ethylene and 1-hexene polymerization reactions was also tested.