Synthesis, characterization and crystal structures of new 1,2,4-triazole based Schiff-bases and their copper(I) complexes

The reaction of 4-amino-5-methyl-2H-1,2,4-triazole-3(4H)-thione (AMTT, 1) with 4-methoxy benzaldehyde and 3-methoxybenzaldehyde in methanol led to the iminic derivatives 4-(4-methoxybenzylideneamino)-5-methyl-2H-1,2,4-triazole-3(4H)-thione (2, L1) and 4-(3-methoxybenzylideneamino)-5-methyl-2H-1,2,4-triazole-3(4H)-thione (3, L2). The reaction of the latter with [(PPh3)(2)CuCl] in methanol solution gave the first Cu-1 complex of 3; [(PPh3)(2)CuCl(L2)] (4) and in chloroform solution the complex [(PPh3)(2)CuCl(L2)](.)2CHCl(3) (5). All compounds were characterized by infrared spectroscopy; elemental analyses as well as by X-ray diffraction studies. Crystal data for 2 at -80 degrees C: space group P2(1)/c with a = 1351.3(3), b = 399.4(1), c = 2225.2(;5) pm, beta = 96.50(2)degrees, Z = 4, R-1, = 0.0667, for 3 at -80 degrees C: space group R3c with a = b = 3020.4(2), c = 708.2(1) pm, Z = 18, R-1 = 0.0435, for 4 at -80 degrees C: space group P2(1)/c with a = 1427.8(1), b = 1129.0(1), c = 2622.8(2) pm, beta = 97.19(1)degrees, Z = 4, R-1 = 0.0517 and for 5 at -80 degrees C: space group P (1) over bar with a = 1230.5(1), b = 1316.1(1), c = 1731.4(1) pm, alpha = 78.14(1)degrees, beta = 86.06(1)degrees, gamma = 64.69(1)degrees, Z = 2, R-1, = 0.0525.