Lutetium alkyl and hydride complexes in a non-cyclopentadienyl coordination environment

Lutetium alkyl complexes [Lu(L)(CH2SiMe3)(THF)(n)], which contain a sulfur-linked bis(phenolato) ligand such as 2,2 '-thiobis(6-tert-butyl-4-methylphenolate) ( L = tbmp, 1) or 1,4-dithiabutanediylbis- 6-tert-butyl-4-methylphenolate) ( L = etbmp, 2), were isolated from the reaction of the lutetium tris(alkyl) complex [Lu(CH2SiMe3)(3)(THF)(2)] with H2L. The monomeric structures of these complexes were confirmed by X-ray diffraction studies, showing distorted octahedral geometry around the metal centre. The reaction of [ Lu( tbmp)( CH2SiMe3)( THF) 2] ( 1) with alcohols ROH ( R = iPr, CHPh2, CPh3) results in the formation of the corresponding alkoxide complexes [ Lu( tbmp)( OR)( THF) n] ( 4 - 6). With PhSiH3 hydride complexes [Lu(L)(mu-H)(THF)(n)](2) (L = tbmp, 7; etbmp, 8) have been prepared in moderate to good yields. They adopt a dimeric form in the solid state as revealed by the X-ray crystal structure of 7. The reactivity of the hydride complexes and their catalytic activity in the ring-opening polymerisation of L-lactide and the hydrosilylation of alkenes are also discussed.