Adduct formation by nickel(II) complexes of S-methyl hydrazine carbodithioate schiff bases with 2,2′-bipyridyl and 1,10-phenanthroline

Synthesis, spectral and thermal studies of 2,2′-bipyridyl adducts of bis(N-alkyl-N-phenyldithiocarbamato)zinc(II)

“…All non-H atoms were refined with anisotropic displacement parameters. Aromatic H atoms were placed in geometrically ) 0.89 Å A 0 from C (21). Crystal data and details of data collection and refinement are given in Table 1.…”

“…The most significant difference between the compound and their corresponding precursor complexes were observed Table 2 Selected bond distances (Å) and angles (°) for complexes 1 and 2. to the parent complexes may be due to two possible reasons; one being the change in coordination geometry from tetrahedral (four coordinate in the starting materials?) to octahedral (six coordinate) [21], which affect the degree of interaction between the dithiocarbamate ligands and the zinc ion leading to a reduction in the vibrational frequency. The second reason could be the transfer of electrons from the nitrogen of the bipyridine ligand to the zinc ion enriching the metal electron density upon the adduct formation [22].…”

Synthesis, Characterization and Thermal Study of Phenanthroline Adducts of Zn(II) and Cd(II) Complexes of bis-N-Alkyl-N-phenyl dithiocarbamates

“…The analytical data of the adducts are given in Table-1 Infrared spectra studies of the adducts: The infrared spectra of the adducts and their precursor complexes were compared and assigned on careful comparison. The thioureide band ν(C-N) for the adducts show a vibrational peak which are considerably lower than the ν(C-N) values of their respective parent complexes and can be ascribed to the change in the coordination geometry from tetrahedral to octahedral 21 . It is also an indication of the transfer of electrons from the nitrogen of the Lewis base (1,10-phenanthroline) to the metal ion causing an increase in electron density upon formation of the adduct 22 .…”

“…The ease of formation of group 12 adducts could be said to follow the trends Cd(II) > Zn(II) > Hg(II). It was observed that the 2,2'-bipyridine adducts 17,21 readily crystallized out of solution compared to the 1,10phenanthroline analogue and could be ascribed to the effect of the rigidity due to the extended conjugation of the 1,10phenanthroline. They are soluble in common organic solvents, such as dichloromethane and chloroform.…”

“…This may be due to the lengthening of the alkyl chain which has been found to be accompanied by a decrease in ν(C-N) 23 . However, in the 1,10phenanthroline adducts of both metals and in the bipyridine adducts of cadmium 21 The spectra of all the compounds show a single peak at the region (1000 ± 70 cm -1 ), indicating that the dithiocarbamate ligands are bidentately coordinated to the metal ions [24][25][26] . The C-H stretching for the methyl, ethyl and butyl groups showed in the region 2930-2928 cm -1 .…”