Synthesis, structure and characterization of zinc(II), copper(II), zinc(II) barium(II) and copper(II) barium(II) complexes of macrocyclic heteronucleating ligands based on isothiosemicarbazide

Abstract

The linear polyether dialdehydes (2-hydroxybenzaldehyde-3-yl)-O-(CH 2CH 2O) n -(3-yl-2-hydroxybenzaldehyde), where n = 3 ( 1), 4 (2), react with S-methylisothiosemicarbazide hydroiodide (or hydrochloride) in the presence of Ba(CF 3SO 3) 2 and zinc(II) acetate and/or copper(II) acetate in methanol/THF to give [ZnBaL 1l(CF 3SO 3)(CH 3OH)] 2·0.5H 2O ( 5). [CuBaL 1(CF 3SO 3) 2] 2 ( 8) and [CuBaL 2(CF 3SO 3) 2] 2 ( 10). Treatment of 5 with AgCF 3SO 3 in methanol and subsequent recrystallization from ethanol results in loss of I − to give [ZnBal 1(CF 3SO 3) 2(H 2O)] 2 ( 6). Removal of the Ba 2− from 6,8 and 10 by using an aqueous solution of guanidinium sulfate affords ZnL 1·H 2O ( 7), CuL 1·2H 2O ( 9) and CuL 2·2H 2O ( 11). The molecular structure of 5 has been determined by X-ray crystallography. Crystal data for 5: monoclinic, P2 1/c,a=9.331(1), b=15.293(2), c=25.940(2) A ̊ , β=97.94(1)°, Z=2 . Electronic and NMR spectra, the magnetic behavior, ESR and mass spectra, and the electrochemistry of the new compounds are discussed.