The molecular structures of copper(II) chloroacetate complexes with 5,7-dimethyl-1,2,4-triazolo-[1,5-alpha]-pyrimidine and 5,7-diphenyl-1,2,4-triazolo-[1,5-alpha]-pyrimidine

Copper(II) complexes of formula Cu-2(CH2ClCOO)(4),(dmtp), (1) and Cu-2(CN2C lCOO)(4)(dptp)(4) (2), where dmtp = 5,7-dimethyl-1,2.4triazolo-[1,5-alpha]- pyrimidine and dptp = 5,7-diphenyl-1,2,4-triazoro-[1,5-alpha]-pyrimidine, w ere obtained. The X-ray diffraction analysis of 1 exhibited the dimeric str ucture with chloroacetate bridges. The coordination sphere of Cu(II) ion is a slightly distorted square pyramid, with 4 equatorial carboxylic oxygens and an axially N(3) bonded dmtp molecule. The distance Cu-Cu is 2.7035(7) A ngstrom and the distance between Cu and O-4 plane is 0.239(1) Angstrom (tow ards the axial ligand). The distances Cu-O are 1.954(2)-1.981(2) Angstrom, Cu-N 2.150(1) Angstrom. The angles O-Cu-O are 87.88(8)-90.56(8)degrees and 166.04(6)-166.07(5)degrees, O-Cu-N 90.08(7)-103.76(7)degrees. The O-4 plane is not perpendicular to the Cu ... Cu line, the angles O-Cu-Cu being 82.04 (5)-84.00(5)degrees and N-Cu-Cu 169.54(4)degrees. Spectroscopic (IR, UV, EP R) and magnetic studies suggested that 2 has the analogous structure to 1. (C) 1998 Elsevier Science Ltd. All rights reserved.