Synthesis and reactivity of bis(phospholyl)neodymium(III) and -samarium(III) chlorides and alkyl derivatives

The reaction of 2,3,4,5-tetramethylphospholylpotassium [C4Me4PK] with [LnCl(3)(THF)(x)] (Ln = Nd, Sm) in a 2:1 ratio gave unsolvated ate complexes of the formula [(C4Me4P)(2)LnCl(2)K]. Crystallisation of the samarium complex from ether afforded a polymeric ether solvate: {[(eta(5)C(4)Me(4)P)Sm(mu(3)-Cl)(2)(mu:eta(5),eta(1)-C4Me4P)K(Et2O)](proportional to)}, which was characterised by X-ray crystallography. Reaction of [(C4Me4P)(2)LnCl(2)K] with [LiCH(SiMe3)(2)] in toluene gave the alkyl complexes [(C4Me4P)(2)LnCH(SiMe3)(2)]; these complexes were most efficiently prepared from [LnCl(3)(THF)(x)], [KC4Me4P] and [LiCH(SiMe3)(2)] in a one-pot procedure. Reaction of [(C4Me4P)(2)LnCH(SiMe3)(2)] with molecular hydrogen gave [(C4Me4P)(2)NdH], when Ln = Nd, whereas, when Ln = Sm, reduction occurred and the already known [(C4Me4P)(2)Sm] was isolated instead.