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(super 13)C nuclear magnetic resonance (NMR) spectroscopy has led to CO hydrogenation over four other catalysts under mild temperature conditions and pressure leading to 1-alkenes as primary products, hence studies were initiated to know more about this phenomenon. The results indicate that fairly simple unmodified or unpromoted metal catalysts give rise to highly regiospecific reactions, and there are complications only when secondary processes start to become significant.

Thiaplatinacycles, resulting from a reversible reaction between nucleophilic platinum(0) complex and dibenzothiophene or benzothiophene or thiophene, undergo hydrodesulfurization with hydrides to yield biphenyl and styrene, along with a platinum-thiol complex. The extent of complex stability during the reverse reaction determines the product yield. In these reactions, both the Pt-C bond and the C-S bond undergo cleavage.

A study was done on the reactivity of a key intermediate in rhodium-catalyzed carbonylation. Results show that the position of alkyl/acyl equilibria in rhodium complexes vary depending on the solvent, ligand environment, charge and nature of the migrating alkyl group. In addition, the high selectivity in unwanted side reactions such as methane formation is favored by rapid migratory insertion and the lower potential equilibrium concentration of the methyl species in rhodium.

A discussion on the properties, characteristics and structural geometries of various calamitic metallomesogens (CM's) is presented. The phase behavior of the CM's is found to be significantly influenced by the ligands. The structural analysis reveals that geometries about the metal center agrees with calamitic mesomorphisms. Various methodologies in reducing the increase in the transition temperature brought about by the incorporation of metals are also explored. The mesophase behavior of the CM's is justified by the dipole-dipole and van der Waals forces.

The question regarding the derivation of true benzene and cyclohexene hydrogenation catalysts from the organometallic precursor [Rh(eta(super 5)-C5Me5)Cl2](sub 2) being homogenous or heterogeneous is addressed. The evidence provided states that Rh(0) nanoclusters are the true hydrogenation heterogeneous catalyst derived from [Rh(eta(super 5)-C5Me5)Cl2](sub 2), at the required more vigorous conditions of 50-100 degree Celsius and 50 atm H2.

The preliminary data concerning the reactivity of the anionic iridium methyl species cis-[Ir(CO)2I3Me](super -) and the first detection of neutral [Ir(CO)3I2Me] is discussed. The results in situ spectroscopic, kinetic, mechanistic and theoretical studies aimed at determining the mechanism by which promoters enhance the activity of an iridium catalyst is presented.

Research was conducted to examine the Fischer-Tropsch (FT) reactions under largely kinetic control, at low temperature, giving primary products substantially free of those from secondary reactions. The addition of 13C2H4 probes to a hydrogenation of 12CO over supported Ru or Rh catalysts was involved. Results based on the 13C NMR spectroscopic analysis of the products reveal the regiospecific formation of the 1-alkene isotopomers which demonstrates, for the first time, the sequential characteristic of the FT polymerization.

Both diazomethane and nitromethane can function as efficient C1 probes. While methylenes derived from 13CH2N2 or 13CH3NO2 probes and methylenes formed from 12CO hydrogenation combine randomly over cobalt, reactions which take place over rhodium Fischer-Tropsch catalysts are quite separate from them. With surface CH2 preferred as an intermediate in CO hydrogenation, it is suggested that the homopolymerization of the probe-derived species may not proceed directly via methylene.

An analysis of pentamethylcyclopentadienyl (eta5-C5Me5, Cp) confirm that, in ambient settings, conspicuous facility accompanies oxygen-enhanced cleavage of C-H in C5Me5RuIII complexes. The dienyl is a spectator ligand in transition metal complexes, and C-H activation of ring methyls is possible under the impact of powerful bases. Extraordinary reactivity is evident for the products such as Ru(II) complexes of tetramethylfulvene.

An analysis reveals that the reaction mechanism for hydrodesulfurization of dibenzothiophene (DBT) involves a reversible insertion of Pt(0) into DBT's C-S bond, yielding a Pt-S-C possessing metallacycle. Hydride reducing agents easily cleave the S-C bond, yielding biphenyl and a Pt-SH complex via triangular transition states. Benzothiophene and thiophene are vulnerable to hydride-induced S-C bond cleavage.