MESITYLINDIUM(III) HALIDE COMPOUNDS - X-RAY CRYSTAL-STRUCTURES OF [INIMES2]2 AND [INI2MES]INFINITY

The reaction of InMes3 with InX3 in 2:1 and 1:2 molar ratios yields InXMes2 [X = Br (2), I (3)] and InX2Mes [X = Br (5), I (6)], respectively. Compound 2 is a dimer in solution, whereas 3 is largely monomeric in benzene and CH2Cl2 but dimeric in the solid state. The dihalides 5 and 6 are polymeric in the solid state; however, 6 is a dimer in solution, while 5 is insoluble in noncoordinating solvents. The structures of 3 and 6 have been confirmed by X-ray crystallography. [InIMes2]2: monoclinic C2/c, a = 26.556 (4) angstrom, b = 17.126 (3) angstrom, c = 8.092 (1) angstrom, beta = 104.70 (1)degrees, V = 3559.7 (9) angstrom 3, Z = 4, no. of observed data 3060, R = 0.032, R(w) = 0.044. [InI2Mes] infinity: monoclinic P2(1)/c, a = 8.234 (2) angstrom, b = 19.657 (3) angstrom, c = 7.703 (1) angstrom, beta = 91.55 (2)degrees, V = 1246.3 (4) angstrom 3, Z = 4 no. of observed data 2805, R = 0.030, R(w) = 0.044. Compounds 2, 3, 5, and 6 are compared to their chloro analogues InClMes2 (1) and InCl2Mes (4).