Preparation and characterization of palladium(II) complexes with N-arylalkyliminodiacetic acids. Catalytic activity of complexes in methoxycarbonylation of iodobenzene

Abstract

The reactions of N-arylalkyl derivatives of iminodiacetic acid (H2Bnida, H2Peida, H2Ppida, o-H2Cbida; Bn = benzyl, Pe = 2-phenylethyl; Pp = 3-phenylprop-1-yl; o-Cb = o-chlorobenzyl) with sodium tetrachloropalladate(II) in aqueous solutions were investigated. Five new palladium(II) complexes [Pd(HBnida)2]·2H2O (1a), [Pd(HBnida)2] (1b), [Pd(HPeida)2] (2), [Pd(HPpida)2] (3) and [Pd(o-HCbida)2] (4) were prepared and characterized by infrared spectroscopy, 1H, 13C and 15N NMR spectroscopy and thermal analysis (TGA/DTA). The crystal structure of 1a was determined by single-crystal X-ray structural analysis. The palladium(II) ion in the molecule of 1a adopts a square planar coordination with two N,O-bidentate N-benzyl-hydrogeniminodiacetate ions. Complex 1a is a trans-isomer. Antitumor properties of the complexes were tested on three human cell lines. The compounds did not significantly inhibit the growth of colon (HCT 116), breast (MCF-7) and lung (H 460) tumor cell lines. All prepared palladium(II) complexes exhibit the acceptable activities towards the methoxycarbonylation of iodobenzene.