Crystallographic Study on Metal(II) Complexes with N-(2-Nitrophenylsulfonyl)glycine

Abstract

The interaction of MII ions (MII =Mn II, CoII, NiII, CuII, ZnII, CdII, PbII) with N-(2-nitrophenylsulfonyl)- glycine (NO2psglyH2) leads to the formation at acidic pH of the complex carboxylate-type M(NO2psgly- O)2.x H2O species. At higher pH the deprotonation reaction of the sulfonamide nitrogen takes place, leading to the formation of the M(NO2psgly-N,O).x H2O species where the ligand acts as a chelating agent toward the metal ion through the carboxylic oxygen and the deprotonated sulfonamide nitrogen. In ternary systems the addition of 2,2′-bipyridine (bpy) allows the deprotonation of the sulfonamide nitrogen also in presence of metal ions such as ZnII, CoII and NiII, which were inactive in the binary system, and the solid compounds isolated are in the M/bpy/L molar ratio 1 : 1 : 1 (MII = CuII , ZnII ) or 1 : 2 : 1(MII = CoII , NiII, CdII). Here we describe the crystal and molecular structures of NO2psglyH2 (1), [Pb(NO2psgly-N,O)]n (2), [Cd(bpy)2(NO2psgly-N,O)].H2O (3) and [Cu(bpy)(NO2psgly-N,O)(H2O)] (4).