Transition metal complexes with thiosemicarbazide-based ligands. Part 60. Reactions of copper(II) bromide with pyridoxal S-methylisothiosemicarbazone (PLITSC). Crystal structure of [Cu(PLITSC−H)H2O]Br•H2O

Abstract

The synthesis and structural characterization of a square-planar copper(II) complex with pyridoxal S-methylisothiosemicarbazone (PLITSC) of the formula [Cu(PLITSC?H)H2O]Br?H2O (1) as the first Cu(II) complex with monoanionic form of this ligand were described. Complex 1 together with two previously synthesized complexes [Cu(PLITSC)Br2] (2) and [Cu(PLITSC)Br(MeOH)]Br (3) were characterized by elemental analysis, IR and electronic spectra and also by the methods of thermal analysis, conductometry and magnetochemistry. [Projekat Pokrajisnkog sekretarijata za nauku i tehnoloski razvoj Vojvodine i Ministarstva nauke Republike Srbije, br. 172014]

Synthesis and crystal structure of copper(II) complexes with pyridoxal S-methylisothiosemicarbazone bearing a new coordination mode

“…Namely, this band is located at 1255 cm -1 in the spectra of the free ligand, while its positions in the spectra of complexes 1 and 2 are at 1305 and 1329 cm -1 , respectively. 19 Finally, in the spectrum of complex 1, the doublet band at 2115 and 2075 cm -1 , corresponds to ν(C-N) vibrations of coordinated and non-coordinated NCS-groups, respectively. Unlike this, in the spectrum of complex 2, only one band is found in the same region (2058 cm -1 ).…”

“…27 In the IR spectra of both complexes, bands in the region 2780-2850 cm -1 could be ascribed to ν(NH + ) vibrations of the protonated pyridine nitrogen atom of the zwitterionic ligand form, which is formed by migration of the hydrogen atom located on a phenolic oxygen atom to a pyridinic nitrogen atom. 9,19 The azomethine band is located at ca. 1560 cm -1 in the spectra of both complexes.…”

“…17 The focus of this research was pyridoxal S-methylisothiosemicarbazone (PLITSC), one of the isothiosemicarbazone ligands. Complexes of some 3d metals with this ligand have been synthesized and structurally characterized, 9,18,19 and it was found that, without exception, this ligand acts as a tridentate N 2 O donor, which is coordinated to the metal ion through the azomethine and isothioamide nitrogen atoms and the phenolic oxygen atom. It should be mentioned that this ligand can be coordinated in three different forms: neutral (zwitterionic), monoanionic (in which deprotonation of isothioureido fragment occurs) and dianionic (with the additional deprotonation of the pyridine nitrogen atom).…”

Synthesis, structure and thermokinetic studies on perchlorate salts of metal complexes containing a formamidine-type ligand

“…The synthesis of aamp [35] and its reaction with metal hydrates was already described [36,37]. Addition of teof alters the reaction route.…”