International Journal of Chemical Research

130-133

Authors: NEBBACHE N., BELHOCINE Y., BENCHARIF M., MEGHEZZI A.

Extended Hückel Molecular Orbital (EHMO) calculations were carried out on octahedral transition metal clusters with general formula [M6X8 iY6 a] (M = Molybdenum; X and Y = π-Donor Ligands) in order to rationalize their electronic structure. In these species the optimal metallic electron (ME) count is of 24 but for many clusters experimentally synthesized, the ME count can vary from 20 to 48 without dramatically altering the architecture of the octahedral cluster. Herein are reported the geometrical parameters and electronic properties, of a series of clusters with 20 to 24 valence electrons per cluster. The calculated characteristics for all the considered structures are in excellent agreement with the experimental ones and requires to learn more about the relationships that exist between their structural arrangement and electronic properties especially the number of electrons available for metal-metal bonding in M6 octahedral clusters.

118-121

Authors: RAVI KANT, TRIPATHI D.M., AMRESH G.

Some new triorganobismuth (V) amide were synthesized by earlier reported method and fully characterized by their elemental and I.R. spectral analysis along with their antimicrobial activity against different pathogenic bacterial and fungal strains and in-vitro antitumor activity against human breast and mammary cancer cell line. It was found that compounds have great potential as antitumor and antimicrobial agents.

126-129

Authors: TEWARI I.C., RAJESH SHUKLA, SUSHMA RANI

The present manuscript deals the kinetics of the oxidation of levulinic acid by Ce (IV) perchlorates in perchloric acid. The reaction follows a first order rate dependence on the Ce (IV) concentration but the value of k1 decreases with the increasing concentration of Ce (IV). Evidence for complex formation between Ce (IV) and levulinic acid was obtained from the Michaelies-Menten reciprocal plots. This was further confirmed spectrophotometrically where the absorption intensity in the wave length region 212 mμ-216 mμ, was intensified as compared to absorption spectra of Ce(IV)perchlorate under identical conditions with an increase in [H+], the rate increases and a plot between [HClO4 ] -1 and k1-1 is a straight line intercepting the ordinate. The reaction shows a positive salt effect. A suitable mechanism has been postulated and the values of activation parameters are reported.