SELENIUM INSERTION INTO THE M-C BOND (M=GA, IN) - SYNTHESES AND X-RAYCRYSTAL-STRUCTURES OF [NP2IN(MU-SENP)](2), [(ME3SICH2)(2)GA(MU-SECH2SIME3)](2), [(MES)C6H7N-CENTER-DOT-GA-MU-SE](2), AND (MES)(2)C6H7N-CENTER-DOT-GASEMES (NP=CH2C(CH3)(3), MES=2,4,6-ME3C6H2, C6H7N=4-PICOLINE)

The independent 1:1 reactions of InNp3 (Np = CH2CMe3) and Ga(CH2SiMe3) (3) with elemental selenium resulted in the formation of novel dimeric compounds with the general formula [R2M(mu-SeR)](2) (M = In, R = Np ( 1); M = Ga, R = CH2SiMe3 (2)) in a nearly quantitative yield. Reaction of GaMes(3) (Mes = 2,4,6-Me3C6H2) with 2 mol of elemental Se, and sub sequent addition of 4-picoline (C6H7N), resulted in the isolation of t hree compounds, [(Mes)C6H7N . Ga-mu-Se](2) (3), (Mes)(2)C5H7N . GaSeMe s (4), and Se(2)Mes(2). Compound 3 is a selenium-bridged dimer with tw o two-coordinate Se atoms and two 4-picoline (C6H7N) molecules in the dimeric unit. In related work, reaction of InNp3 with S2Ph2 afforded t he dimeric compound [Np2In(mu-SPh)](2) (5) with elimination of NpSPh. The synthesis and characterization of 1-5, including their solid-state structures, are presented.