Phosphane-catalyzed reactions of LAlH2 with elemental chalcogens; preparation of [LAl(μ-E)2AlL] [E = S, Se, Te, L = HC{C(Me)N(Ar)}2, Ar=2,6-iPr2C6H3]

Addition of catalytic amounts of a phosphane to a reaction mixture containing LAlH2 [2; L = HC{C(Me)N(Ar)}(2), Ar = 2,6-iPr(2)C(6)H(3)] and elemental Se or Te resulted in the formation of poorly soluble [LAl(mu-Se)(2)AiL] (3) and [LAl(mu-Te)(2)AlL] (4), respectively. The sulfur analogue [LAl(mu-S)(2)AlL] (5) could not be obtained from the direct reaction of 2 with elemental sulfur; consequently, its synthesis was successfully achieved from the reaction of [LAlH2] and [LAl(SH)(2)]. A possible mechanism for the formation of [LAl(mu-Se)(2)AlL] and [LAl(mu-Te)(2)AlL] is discussed. The molecular structures of compounds 3-5 were determined by X-ray structure analyses. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004).