Synthesis and structure of Cu(II) and Pd(II) coordination compounds with chiral α-thiooxime, a derivative of natural terpenoid (−)-α-pinene

Abstract

The paramagnetic complex Cu(HL)Cl2(I) (μeff = 1.88 μB) and the diamagnetic complex Pd(HL)Cl2(II) with chiral α-thiooxime, a derivative of natural terpenoid (−)-α-pinene (HL), were synthesized. The crystal structures of these complexes were determined from single-crystal X-ray diffraction data (X8 APEX diffractometer, MoK α radiation, 2975 F hkl , R = 0.0258 for I and 3270 F hkl , R = 0.0222 for II). The crystals of complex I are monoclinic, a = 9.3376(3) A, b = 6.8619(2) A, c = 14.6540(5) A, β = 97.814(1)°, V = 930.22(5) A3, Z = 2, ρcalc = 1.513 g/cm3, space group P21. The crystals of complex II are orthorhombic, a = 7.0084(6) A, b = 9.2113(9) A, c = 29.081(3) A, V = 1877.4(3) A3, Z = 4, ρcalc = 1.651 g/cm3, space group P212121. The structures are composed of mononuclear molecules. The coordination cores MNSCl2 (M = Cu, Pd) are tetrahedrally distorted squares. According to NMR data, complex II has a similar structure in a CDCl3 solution. The intermolecular contacts in structure I generate supramolecular polymeric ribbons lying parallel to axis b. No short intermolecular contacts are present in complex II.