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The structural and spectroscopic characterization of a series of trinuclear and tetranuclear vanadium(III)/carboxylate complexes of acetate and related derivatives are described. The results have shown that these complexes are not purely solid-state phenomena but are also present in solution.

The applicability of transition-metal (TM)-monosubstituted Keggin polyoxometalates (POMs) and TM-carboxylate cationic complexes for the synthesis of new magically attractive hybrid compounds are explored. Electron paramagnetic resonance studies indicate that both the supported [Cu(sub 2)(ac)(sub 2)(phen)(sub 2)(H(sub 2)O)](super 2+) complexes and the copper(II)-monosubstituted Psos are magnetically isolated.

A new approach is presented for the preparation of metal-organic lanthanide sol-gel precursor and its application for the production of coated conductors. It is found that there are two separate structures for hydrated yttrium acetates, which is an intermediate in the building of ceramic oxide layers for coated conductors.

The monooxo Re(V) core is conveniently stabilized by tripodal scorpionate ligands comprising carboxylate or sulfonate tails, giving a series of intermediate complexes of the type Re(O)(NNO)Cl(X) (X=Cl), whose structure depends on the type of NNO ligand and solvent utilized. The presence of 3,5-substituted pz in the NNO framework is crucial for further replacement of monodentate groups giving stable '3+2' mixed ligand groups.

The developments related to enantioselective [2 + 1]-cycloaddition reactions of ethyle diazoacetate are described. The various useful applications of mechanistic insight, which is a discovery of a unique chiral catalyst are discussed.

A detail study was carried out to examine the chemical features, such as substrate stability, product distribution, and substrate generality, and the reaction mechanism of Bronsted superacid-catalyzed cyclization reactions of aromatic ring-containing acetoacetates ([beta]-ketoesters). The results showed that intervention of the trication contributed significantly to the activation of the cyclization of arylacetoacetates in strong acid, and the electron-withdrawing nature of the O-protonated ester functionality significantly increased the electrophilicity of the ketone moiety.

The application of Lewis acid for the catalysis of the cyclization reaction of the methyl phenyldiazoacetates with an ortho-imino group is determined. The reaction is shown to be extremely useful for the production of various substituted indoles.

Several studies are conducted to explain the synthesis, as well as the properties of the various [gamma]-silyl cyclobutyl carbocations. These cations are shown to be much more stable than the [beta] cations and hence can be used for numerous applications.

A highly regio- and stereoselective oxidative hydroacetoxylation of 1,2-allenylic sulfoxides is developed that has produced 1-sulfonyl-1-alken-3-yl acetates. The X-ray diffraction study has shown that the reaction has proceeded via a 5-membered cyclic intermediate and the [super -]OAc has attacked the chiral carbon atom.

The article presents a new approach, which is used for the isothermal synthesis of a new organically templated homochiral material, which exhibits the acetate-pillared cobalt-camphorate architecture. The methodology is shown to be extremely useful for the development of a large number of functional materials.

A gold(I)-catalyzed cycloisomerization of 1,7- and 1,8-enyne propargylic acetates to obtain cyclopropyl derivatives containing seven- and eight-membered rings is reported. The reaction could also be used for the synthesis of a new allocolchicinoid having a cyclopropane ring fused to the B seven-membered ring at the C6-C7 positions.

The process of infrared-ultraviolet double resonance spectroscopy is employed to study the structure of the phenylacetate-water complex. The discussed complex is shown to be formed as a result of the cooperativity existing between two sets of hydrogen bonds.

A one-pot procedure is developed for the synthesis of 2-alkyl-2-arylcyanoacetates based on a Pd[(OAc).sub.2]/DPPF (DPPF = 1,1E-diphenylphosphino ferrocene)-catalyzed enolate arylation followed by in situ alkylation. This method has tolerated a range of aryl and heteroaryl bormides and has provided entry into a variety of 2-alkyl-2-arylcyanoacetates in good yields.

An analysis explains the various effects of strongly acid microemulsions on the acid hydrolysis mechanism of different esters. The results show that the hydrolysis rate constant at the interface is inversely related to the water content of the system.

A chiral intermediate derived from the nucleophilic addition of L-proline as secondary amine to ketone is first synthesized in situ in the presence of cobalt (nickel) acetate, which provides a strategy for the syntheses of tertiary carbinol compounds. Two chiral Co/Ni clusters bearing a rare flattened tetrahedral configuration are obtained with the chiral intermediate as a ligand.

The thermal and mesomorphic properties of [Ln(Li(super c12)-CF(sub 3)CO(sub 2))(sub 3)], 14 complexes is investigated using combination of thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), polarized light microscopy (PLM), and small-angle d(SAXS). Except for loss of cocrystallized water molecules in two of the complexes, TGA shows that complexes do not decompose prior to isotropization, which occurs around 208-248 degree Celsius.

A discussion is presented on the synthetic and mechanistic dimensions that govern the range, availability and utility of diazirines. The diazirines are ideal precursors for spectroscopic studies of carbenes, either by matrix isolation or in solution by laser flash photolysis.

A combination of kinetic isotope effects, theoretical calculations and dynamics trajectories were used to study the C(super 2)-C(super 6) (Schmittel)/ene cyclization of enyne-allenes. The isotope effect (k(sub CH3)/k(sub CD3)) was found to be approximately 1.43 for the cyclization of allenol acetate.

Picosecond and nanosecond time-resolved resonance Raman spectroscopy have been used to study the dynamics and structure of the phototrigger compound p-hrdroxyphenacyl acetate (HPA) in acetonitrile solution. The results demonstrate the utility of applying ultrafast vibrational spectroscopy to study the mechanism of the photorelease process in phototrigger compounds.

Structural theme in polyketide/macrolide natural products is one or more polyol chains derived from the biosynthesis coupling of acetate and propionate units. Stereo controlled approaches to the synthesis of such structures, chemists have relied heavily on aldol addition reactions.

A new method for synthesis of [1,4]oxazepin-7-ones from readily available aldehydes and alpha-amino alcohols is developed using the Baylis-Hillman reaction as the key step. The Baylis-Hillman reaction is a valuable C-C bond forming reaction in organic synthesis, which has found widespread application in recent times.

The syntheses, crystal structures, and electronic properties of acetate- and propionate bridged 1-D [Pt (2.2+)(sub 2)](sub infinity) chain complexes, as the first report of 1-D mixed-valence chains consisting of dinuclear cations, are described. The combined results deny a simpler description of Pt(2.25+)(sub infinity) (formally [Pt(II)3 Pt(III)](sub infinity) for the present systems, and rather support the reported mixed-valency of Pt (2.2+)(sub infinity).