Conformational studies of some potentially bidentate thiosemicarbazones and related complexes of zinc(II)

Abstract

N.m.r. spectra of some potentially bidentate thiosemicarbazones, NR³H·CS·NH·N:CR²R¹(L: R¹,R²= H, Me, Ph, or R¹R²= C₆H₁₁; R³= H or Ph), and their complexes [ZnCl₂L] or [ZnCl₂L₂] have been measured. The results are compared with semiempirical CNDO/2 total-energy calculations. Only one conformer, containing an intramolecular hydrogen bond, is present in solution. All the zinc(II) complexes are tetrahedral. The possible formation of complexes in which the ligand is bidentate is discussed.