Synthesis and characterization of some zinc, cadmium and mercury(II) derivatives of bis(4-methylpyrazol-1-yl) alkanes

Abstract

The interaction between bis(4-methylpyrazol-1-yl)methane, L, and various MX 2 (M = Zn, X = Cl, Br or I; M = Cd, X = Cl, I or NO 3; M = Hg, X = Cl, Br, I, CN or SCN) gives the 1:1 adducts [L]MX 2, which are air- and thermally stable. The ligand also gives 2:1 {[L] 2Zn(CF 3SO 3) 2·2H 2O, [L] 2Zn(NO 3) 2·3H 2O, [L] 2Cd(ClO 4) 2·H 2O, [L] 2Hg(CF 3CO 2) 2} and 3:1 {[L] 3Zn(ClO 4) 2, [L] 3Zn(BF 4) 2, [L] 3Zn(CF 3CO 2) 2·H 2O, [L] 3Cd(BF 4) 2·H 2O, [L] 3Hg(ClO 4) 2·H 2O} adducts with good acceptors. All the complexes have been characterized from analytical and spectral (IR, far-IR, 1H and 13C NMR) data. The adduct [L]HgCl 2, stable in pyridine solution, readily reacts with PPh 3 and 2,2′-bipyridyl (Bipy) to yield (PPh 3) 2HgCl 2 and (Bipy)HgCl 2, respectively. Comparison is made with results obtained with group 12 derivatives of other poly(azol-l-yl)alkanes.