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

Abstract

The interaction of M^II ions (M^II =Mn ^II, Co^II, Ni^II, Cu^II, Zn^II, Cd^II, Pb^II) 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 Zn^II, Co^II and Ni^II, which were inactive in the binary system, and the solid compounds isolated are in the M/bpy/L molar ratio 1 : 1 : 1 (M^II = Cu^II , Zn^II ) or 1 : 2 : 1(M^II = Co^II , Ni^II, Cd^II). 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).