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Draksha,
- Studies on the Effect of Tetramethylene Sulfoxide and Various Anions on the Stereochemistry of Lanthanide (III) Coordination Compounds of 4[N-(4’-Ethylbenzalidene) Amino]-Antipyrinesemicarbazone
Authors
1 Department of Chemistry, Vishveshwarya Institute of Engineering and Technology, Dadri -G. B. Nagar (U.P.) 203 207, IN
2 Department of Chemistry, S. S V. P. G. College, Hapur (U.P.), IN
Source
Asian Journal of Research in Chemistry, Vol 4, No 6 (2011), Pagination: 908-916Abstract
The structural chemistry of the lanthanide (III) compounds has recently undergone considerable development and a wide variety of coordination numbers and geometries have been observed. The coordination numbers exhibited by the tripositive lanthanide ions usually vary from 6 to 10. However, other examples of lanthanide (III) complexes with more than 10- coordination number have also been reported in the literature. In the present studies the effect of tetramethylene sulfoxide (TMSO) on the stereochemistry of the coordination compounds of trivalent lanthanides derived from 4-[N-(4'-ethylbenzalidene) amino] antipyrine semicarbazone (EBAAPS) is reported. The general composition of these coordination compounds is LnX3.n (EBAAPS).TMSO (Ln = La, Pr, Nd, Sm, Gd, Tb, Dy or Ho ; X = NO3 , n = 1, X = ClO4 or NCS, n =2). All these compounds were characterized by elemental analysis, molar mass, molar conductance, magnetic susceptibility, infrared and electronic spectra. The infrared studies reveal that the EBAAPS acts as a neutral tridentate (N,N,O), while TMSO is coordinated to the central metal ion via its lone oxygen atom. In nitrato complexes, the nitrates ions are bicovalently bonded, while thiocyanate is coordinated through hard Natom. Perchlorato ions are not participating in coordination and are present outside the coordination sphere. From electronic spectral data, nephelauxetic effect (β), covalence factor (b1/2), Sinha parameter (δ%)and the covalence angular overlap parameter (η) has been calculated. Antibacterial properties of these compounds were also studied. Thermal studies of these compounds were studied by thermogravimetric analysis. The present studies reveal that the coordination number of lanthanide (III) in the present compounds is either 7 or 10 depending on the nature of anions.
Keywords
Lanthanides, Semicarbazone, Diphenyl Sulfoxide, Coordination Compounds.
- Synthesis, Characterization and Biological Evaluation of Some Cobalt (II), Nickel (II) and Copper (II) Complexes of 4[N(2’,4’-Dichlorobenzalidene) Amino]Thiosemicarbazone and 4[N(2’,4’Dinitrobenzalidene) Amino] Thiosemicarbazone
Authors
1 Department of Chemistry, Vishveshwarya Institute of Engineering and Technology, Dadri -G. B. Nagar (U.P.) 203 207, IN
2 Department of Chemistry, S. S V. P. G. College, Hapur (U.P.), IN
Source
Asian Journal of Research in Chemistry, Vol 4, No 6 (2011), Pagination: 976-983Abstract
Of the sulphur donor ligands, thiosemicarbazones have perhaps not been given as much attention as dithiophosphate, dithiocarbamates, dithiolates, dithio--diketonates, dithiooxamide or xanthates. Although many thiosemicarbazones possess a wide spectrum of medicinal properties including activity against influenza, protozoa, small pox, certain kinds of tumour, tuberculosis, leprosy, bacterial and viral infections, psoriasis,, rheumatism and tripamosomiasis, cocidiosis, malaria and have been suggested as possible pesticides and fungicides. Their activity has frequently been thought to be due to their ability to chelate trace metals. In recent years a number of review articles have been appeared on various metal-coordination complexes of thiosemicarbazones. In research of new thiosemicarbazones, two new thiosemicarbazones i.e., 4[N-(2',4'-dichlorobenzalidene)amino]antipyrine thiosemicarbazone (DCBAAPTS) and 4[N- (2',4'-dinitrobenzalidene)amino]antipyrine thiosemicarbazone (DNBAAPTS) have been synthesized and characterized. The complexing abilities of both thiosemicarbazones toward cobalt(II), nickel(II) and copper(II) metal salts have been explored. The newly synthesized complexes have the general composition [M(L)·H2O·X2] (M = Co ,Ni or Cu; X = Cl, Br, NO3, NCS or CH3COO; L = DCBAAPTS or DNBAAPTS). All the complexes were characterized by elemental analyses, molar mass, molar conductance, magnetic susceptibility, infrared and electronic spectra. These metal complexes were screened for their antibacterial and antifungal activities on different species of pathogens, fungi and bacteria and their biopotency has been discussed.