Synthesis and structure of copper(II) complexes with methyl [(pyrazolo-1-carbothioyl)-amino]propionate derivatives

Methyl 3-[(3,5-dimethylpyrazole-1-carbothioyl)-amino]propionate (L-1) and the optically active derivative of natural monoterpene (+)-3-carene, (3bS,4aR)-3-[(3,4,4-trimethyl-3b,4,4a,5-tetrahydro-cyclopropa[3,4]cyclopenta[1,2-c]pyrazole-1-carbothioyl)-amino]propionate (L 2), are synthesized. The paramagnetic (CuLCl2)-Cl-1 (1) and [(Cu2L2Cl4)-Cl-2] (II) complexes are obtained. According to the X-ray diffraction data, in mononuclear complex I, the L-1 molecule performs a bidentate-cyclic function due to the coordination of the S atom of the C=S group and the N atom of the pyrazole cycle. The CuCl2NS coordination polyhedron is a distorted tetrahedron. Two molecules of complex I form an associate due to weak (CuS)-S-... interactions. Compound II is binuclear due to the bridging function of two Cl- ions, and analogous functions of the L-1 and L-2 ligands. The coordination polyhedron in complex II is CuCl3NS. The mu(eff) values for compounds I and II are equal to 1.81 and 1.79 913, respectively, and are constant in the interval from 78 to 300 K, indicating that noticeable exchange interactions between unpaired electrons of the Cu2(+) ions are absent. The EPR spectra of the complexes in the solid phase are examined.