Synthesis, crystal structure and properties of three different derivatives of bis[di(2-pyridyl)methanediol]copper(II), [Cu(bpmd)2]2+¶

Abstract

In an attempt to obtain ternary copper(II) [Cu(II)] complexes where bis(2-pyridyl) ketone (bpk) could induce the fac-O2 + N(apical) conformation in the HL2− form of two different nitrilotriacetates (HNTA2− and HDNTA2−), we obtained [Cu(bpmd)2][Cu(HNTA)2] · 2H2O (1) and [Cu(bpmd)2](H2DNTA)2 · 4H2O (2) where bpmd is di(2-pyridyl)methanediol. On this basis, the salt [Cu(bpmd)2][Cu(IDA)2] · 6H2O (3) [iminodiacetate (IDA) ligand] was also obtained. The crystallographic studies of these compounds revealed that the common cation of these salts results from aquation of bpk in the aqueous media. The aquation of bpk is unexpectedly fast in the case of 1 because crystals appeared on the same day of the synthesis. ¶This article is dedicated to Professor Alfredo Mederos for his contribution to the coordination chemistry.