Cocrystallization of (μ-S2)2- and (μ-S)2- and formation of an [η2-S3N(SiMe3)2] ligand from chalcogen reduction by (N2)2- in a bimetallic yttrium amide complex.

The reactivity of the (N(2))(2-) complex {[(Me(3)Si)(2)N](2)Y(THF)}(2)(μ-η(2):η(2)-N(2)) (1) with sulfur and selenium has been studied to explore the special reductive chemistry of this complex and to expand the variety of bimetallic rare-earth amide complexes. Complex 1 reacts with elemental sulfur to form a mixture of compounds, 2, that is the first example of cocrystallized complexes of (S(2))(2-) and S(2-) ligands. The crystals of 2 contain both the (μ-S(2))(2-) complex {[(Me(3)Si)(2)N](2)Y(THF)}(2)(μ-η(2):η(2)-S(2)) (3) and the (μ-S)(2-) complex {[(Me(3)Si)(2)N]2Y(THF)}(2)(μ-S) (4), respectively. Modeling of the crystal data of 2 shows a 9:1 ratio of 3:4 in the crystals of 2 obtained from solutions that have 1:1 to 4:1 ratios of 3/4 by (1)H NMR spectroscopy. The addition of KC(8) to samples of 2 allows for the isolation of single crystals of 4. The [S(3)N(SiMe(3))(2)](-) ligand was isolated for the first time in crystals of [(Me(3)Si)(2)N](2)Y[η(2)-S(3)N(SiMe(3))(2)](THF) (5), obtained from the mother liquor of 2. In contrast to the sulfur chemistry, the (μ-Se(2)(2-) analogue of 3, namely, {[(Me(3)Si)(2)N](2)Y(THF)}(2)(μ-η(2):η(2)-Se(2)) (6), can be cleanly synthesized in good yield by reacting 1, with elemental selenium. The (μ-Se)(2-) analogue of 4, namely, {[(Me(3)Si)(2)N]2Y(THF)}(2)(μ-Se) (7), was synthesized from Ph(3)PSe.