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The study describes the synthesis, structure, as well as the upconversion of three new organically amine templated uranium phosphites. These complexes are found to give out blue emission, in addition to the antiferromagnetic behavior.

The synthesis, structural characterization, and electronic properties of a new series of high-spin six-coordinate dihalide mononuclear [Mn.sup.II] complexes [Mn(tpa)[x.sub.2]] (tpa = tris-2-picolylamine and X = I, Br, Cl) are reported.

The first stereoselective synthesis of (-)-(ent)-julifloridine, the antipode of naturally occurring alkaloid (+)-julifloridine, from L-alanine is reported. (-)-(ent)-Julifloridine is obtained from Sern oxidation of piperidine, followed by Wittig olefination and hydrogenation/debenzylation.

A kinetic and computational analysis of the palladium(II)-catalyzed asymmetric allylic trichloroacetimidate rearrangement is presented. The study leads to the development of a model, where in the planar chirality of the catalysts controls the enantioselectivity and hence can be used for rational designing of more enantioselective catalysts.

Exact quantum mechanical state-to-state differential and integral cross sections and their energy dependence are calculated on an accurate N[H.sub.2] potential energy surface (PES) by using Chebyshev wave packet method. The analysis of the trajectories has revealed that the backward bias in the differential cross section stems from the fast insertion component of the reaction, augmented with some flux from the abstraction channel, particularly at high collision energies.

A study to determine the differences between the spectroscopic data of the isolated and synthetic samples of the marine natural product (+)-elisabethadione and (+)-elisabethamine was conducted. Results concluded that the published NMR spectral data for natural (+)-elisabethadione do not fit the assigned structure and raises doubt about the (+)-elisabethamine structure.

The nanosecond equilibrium method is employed to describe the determination of the standard potential of alkyl primary amines. The versatility and accuracy of the method shows that while it is an alternative to the classical and modern electrochemical approaches, it is also a powerful tool for quantifying inductive and/or solvation effects in related family of compounds.

The chemistry of bis(2-pyridylmethyl)-amine (BPMA) and its N-benzyl derivative, BBPMA with gold(III) and the comparison of the structures of amine and amido derivatives of gold(III) are described. The ligands BBPMA and BPMA coordinate to gold(II) to give cationic complexes [[AuCl(BBP-MA)].sup.2+] and [[AuCl(BPMA)].sup.2+] and the gold center is strongly polarizing.

A novel one-pot organocatalytic selective process is described for the cascade synthesis of highly substituted o-hydroxydiarylamines and o-pyrrolidin-1-yldiarylamines. The direct combination of amine-catalyzed cascade Knoevenagel/Michael/aldol condensation/decarboxylation and cascade enamine amination/isoaromatization of alkyl acetoacetates, aldehydes and nitrosoarenes has provided the highly functionalized anilines with high yields.

The reaction methodology for intermolecular C-H amination of benzylic and 3 degree C-H bonds using the starting alkane as the limiting reagent is presented. Results reveal that C-H amination follows through a concerted asynchronous two-electron oxidation pathway.

The enantiomeric recognition of amines by voltammetry using electroactive macrocyclic molecules, nitroazophenolic crown ethers, is reported. The oxidation potential of the nitroazophenol moiety in nitroazophenols with 18-crown-6 sensitively depends on the structure of alkyl amines. Based on this phenomenon, enantiomeric amines and even the quantitative assay of the R/S ratio in enantiomeric mixtures can be selectively recognized by using 18-crown-6 azophenol (3-H) with chiral centers. In the case of phenylglycinol, the association constants (K) of 3-H for the R and S forms have an R/S value of 3.5. The peak potential of the R form in square-wave voltammograms reproducibly differs from that of the S form by 32 mV, within which the peak potential linearly varies with the enantiomeric ratio. Free energy perturbation and molecular dynamics simulation provide deeper understanding of the enantiomeric recognition in this system. The theoretical analysis indicates that the free energy difference between diastereomeric complexes agrees well with the experimental results, and the [pi]-[pi] of charge--charge interaction plays a key role in enantiomeric recognition.

A powerful approach to relative quantification by mass spectrometry is to employ labeling reagents that target specific functional groups in molecules of interest. A quantitative comparison of two or more samples may be readily accomplished by using a chemically identical but isotopically distinct labeling reagent for each sample. The samples may then be combined, subjected to purification steps, and mass analyzed. Comparison of the signal intensities obtained from the isotopically labeled variants of the target analyte(s) provides quantitative information on their relative concentrations in the sample. In this report, we describe the synthesis and use of heavy and light isotopic forms of methyl acetimidate for the relative quantification of amine-containing species. The principal advantages of methyl acetimidate as a labeling reagent are that the reaction product is positively charged and hydrophobicity is increased, both of which enhance electrospray ionization efficiency and increase detection sensitivity. The quantitative nature of the analysis was demonstrated in model metabolomics experiments in which heavy and light labeled Arabidopsis extracts were combined in different ratios. Finally, the labeling strategy was employed to determine differences in the amounts of amine-containing metabolites for Arabidopsis seeds germinated under two different conditions.

A simple copper-based catalytic system which was developed for the carbon-hydrogen amidation reaction is reported. It was found that the complex T[p.sup.Br3]Cu(NCMe) displays a singular catalytic activity toward the nitrene-transfer reaction and the subsequent insertion of such units into the carbon-hydrogen bond of a series of substrates, including benzene, cyclohexane, alkyl aromatics, and cyclic ethers.

Semiconductor CdS and CdSe nanostructures with complex form such as urchin-like nanoflowers, branched nanowires and fractal nanotrees were synthesized via a facile solvothermal approach in a mixed solution made of diethylnetriamine (DETA) and deionized water (DIW). The results showed that the morphologies of CdS and CdSe nanocrystals can be controlled via tuning the volume ratio of DETA and DIW suggesting that the photocatalytic property of CdS nanostructures is related to its unique structural feature.

Coating of substrates with polyelectrolyte multilayers terminated with poly(acrylic acid) (PAA) followed by activation of the free -COOH groups of PAA provides a surface that readily reacts with amine groups to allow covalent immobilization of antibodies. The use of this procedure to prepare arrays of antibodies in porous alumina supports facilitates construction of a flow-through system for analysis of fluorescenfly labeled antigens. Detection limits in the analysis of Cy5-labeled IgG are 0.02 ng/mL because of the high surface area of the alumina membrane, and the minimal diameter of the substrate pores results in binding limited by kinetics, not mass transport. Moreover, PAA-terminated films resist nonspecific protein adsorption, so blocking of antibody arrays with bovine serum albumin is not necessary. These microarrays are capable of effective analysis in 10% fetal bovine serum.

The synthesis and charge transfer properties of triarylamine-oligothiophene-perylenemonoimide dendrimers, TPA(T((sub 2)-PMI)(sub 3) and TPA((T(sub 4)-PMI)(sub 3), are described. The presence of the triarylamine and/or the proximity of the oligothiophenes improve the donor capabilities of the oligothiophenes unit slightly and enhance its conjugation as seen in the absorption spectra and the transient of the radical cation.

The photoreduction of 4,4'-bipyridine (44BPY) by diazabicyclo[2.2.2]octane and triethylamine is investigated by using picosecond transient absorption and time-resolved resonance Raman spectroscopy in various acetonitrile-water mixtures. The results show that 44BPY is hydrogen bonded to water molecules as soon as water reaches a concentration of 10% in volume.

A route is developed to a structural analogue of [5]HELOL, a helically grooved sensor of remote chirality. It gives the material enantiomerically pure and in multigram quantities.

The photoreactions of [60]fullerene with aromatic tertiary amines such as N,N-dimethylaniline and N,N-dimethyl-1-naphthylamine gave two or three types of [60]fullerene adducts. The reaction efficiency in the series of p-substituted N,N-dimethylanilines remarkably increased with increasing electron-donating properties of aromtic tertiary amines employed.

Cyanide-catalyzed aldimine coupling is employed to synthesize compounds with 1,2-ene-diamine and alpha-imine-amine structural motifs, 1,2,N,N'-tetraphenyletheylene-1,2-diamine and plusmn-2,3-di(2-hydroxyphenyl)-1,2-dihydroquinoxaline, respectively. Theoretical investigations into isomeric preferences for products of the benzoin condensation reveal that the hydroxy-ketone motif is favored by 10-15 kcal/mol over the ene-diol tautomers.

The molecular structure, infrared spectrum and UV photochemistry of 2-methyl-2H-tetrazol-5-amine (2MTA) isolated in solid argon were investigated. The infrared spectrum of matrix-isolated 2MTA was fully assigned and correlated with structural properties.

An electride that is stable to auto-decomposition at room temperature is synthesized. The key is the theoretically directed synthesis of a per-aza analogue of cryptand[2,2,2] in which each of the linking arms contains a piperazine ring.

Benzydamine, a molecule with an N,N-dimethylaminopropoxyl side chain, showed a fragmentation pattern in Q1 scans in electrospray ionization (ESI) on a triple quadrupole mass spectrometer. By using a smaller model molecule with the kinetic energy release measured for the corresponding reaction, it is demonstrated that an ion-neutral complex composed of the N,N-dimethylazetidine cation and a neutral counterpart is involved.

The cavitand provides two identical receptor sites formed by two dipicolylamine groups facilitating the simultaneous binding of two anions. Intermolecular bindings of anions between two protonated dipicolylamine groups is indicated on the basis of the comparison to a structurally similar monomeric analogue and by semiempirical PM3 molecular modeling.

A detailed account on chiral secondary amine salt that promoted enantioselective intramolecular formal aza-[3 + 3] cycloadditions is described. The dependence of enantioelectivity on the structural feature of these chiral amines is investigated.

A study shows that the relatively stable Cr(V) hydroximato complexes are formed during the reactions of hydroxamic acids with Cr(VI) in polar aprotic solvents. This study also isolates a five-coordinate oxochromate(V) complex of benzohydroxamine acid in a pure form.

A new carbohydrate-based radiopharmaceutical is developed by complexing a series of tridentate sugar-pendant 2.2'-dipicolylamine ligands to the {M(CO)3}(super +) [(super 99m)Tc/Re] core. The study proves that the carbohydrate moieties remain pendant in solution and in the solid-state thereby increasing the potential for interaction with hexose transport and metabolic pathways in vivo.

A comparison was made between the experimental and the Becke exchange functional and nonlocal LYP correlation functional (B3LYP) relative gas-phase basicities and proton affinities of a series of 9 amine, 3 alcohol, and 3 alkanolamine molecules. Calculations on dimer forms indicate that the alkanolamines, diamines, and 1,2-ethanediol form stable proton-bound dimers.

Preparation of three new amine-templated zinc phosphates, AU-I, AU-II, and AU-III from the same reaction mixture and treated at varying temperatures is presented. Observations reveal that there is an increase in the structural size or density of the three materials along with the temperature of the synthesis.

The chemical viability of rG-to-aG formation through rG addition to a synthetic cyanoamine derivative is demonstrated. This establishes an alternative to the common hypothesis that assumes G-to-G cross-link formation occur by direct nucleophilic aromatic substitution of a guanosinediazonium ion by a guanosine.

The interaction of amine-terminated polyamido(amine), PAMAM, dendrimer with copper(II) ions determined by extended X-ray absorption fine structure (EXAFS) is reported. The results suggest that the model consisting of the copper(II) ion forming five- and six- membered rings by chelating with the primary amine, amide, and tertiary amine nitrogen doors of the PAMAM dendrimer could describe the experimental EXAFS data well.

Defining quantatively the intrinsic origin of the strength of gas-phase Lewis basicity of the cyclic amines, in particular, based on the local electron-donating ability of the amine nitrogen atoms. The present work shows that a well-defined local property of the amine nitrogen atoms can aid understanding of the Lewis basicity of the cyclic amines.

The enolpyridine, OH-ketoenamime, NH equilibrium in crystals of 1,3-bis(pyridin-2-yl)propan-2-one is studied using temperature-dependent single-crystal x-ray diffraction. The report states that the theoretical model suggest the appearance of concerted hydrogen motions, which are unique to the dimer and can be used to quantify the effect of the supramolecular interaction on the hydrogen population in the crystal.

The synthesis of tris (2,6-dihydroxyphenyl) amine diborate is described and a study of the nature of bonding along its B-N-B axis is reported. Calculations indicated that a bond-switch mechanism, involving a 3c-2e B...N...B transition structure is not likely.

'Planar-chiral' derivatives of 4-(dimethylamino)pyridine (DMAP), a highly versatile nucleophilic catalyst, is developed that are effective in various processes, including the Staudinger synthesis of beta-lactams, the acylation of silyl ketene acetals, and the kinetic resolution of amines.

Ionophore-siderophore host-guest assemblies composed of 18-crown-6 and ferrioxamine B,benzo-18-crown-6 and ferrioxamine B and cis-syn-cis-dicyclohexno-18-crown-6 and ferrioxamine B are successfully crystallized. These structures are determined by single-crystal x-ray diffraction.

A study of the infrared and ultraviolent spectroscopy of the hormone melatonin, N-acetyl-5-methoxytryptamine (MEL) was conducted, which contained a single, methyl-capped amide group. The study identified transitions due to five conformers of MEL, three trans-amides, and two minor cis-amide conformers.

The bonding of amine with pentathiepin to promote its decomposition is described. A mechanistic insight into the process that gives rise to pentathiepin biological activity is provided.

The results relating to the deprotonation of 1-benzyl-1-methoxy-2-nitroethylenes, by amines, which include structural features in the nitroalkanes are reported. The question addressed is whether the special structural features affect the actual size of the transition state imbalance and/or its manifestation in terms of alpha and beta values.

A different approach to amino acids based on an expeditious route to enantiopure allylic amines is reported. This is an efficient and general method toward both the L and D configuration of this class of alpha-substituted glycines, as demonstrated by the synthesis of N-protected L and D (1-adamantyl)-glycines.

Secondary amines, which are plant growth regulators, growth promoters, antibiotics or antitumor agents, have been used as chiral auxiliaries for asymmetric catalysis as resolving agents. A general microscale method, which is applicable for both cyclic as well as acyclic aliphatic amines as well as aromatic, using zinc porphyrin tweezer, to determine the absolute stereochemistry is described.

A study of the nature of electron delocalization while questioning the abnormally large torsional angle theta of N-phenylmethylene-3-pyridineamine with a new program for energy partitioning is presented. The results show that the energy partitions, the pi-pi, pi-sigma, and nonbonded sigma-sigma interactions between fragments are always destabilization, and it is the nonbonded sigma-sigma interaction, rather than the pi-pi interaction, that distorts stilbene-like species away from their planar geometry

The stereochemical investigation is conducted to give students the combined experience of chemical synthesis of amines and N-heterocycles and structural stereohemical analysis using NMR spectroscopy. Students are introduced to the concept of topicity-stereochemical relationships between ligands within a molecule by synthesizing N,O-acetals.

Several molecular dynamics (MD) simulations are used to compare the three atomistic force fields or to predict the physical properties of dimethylnitramine (DMNA), which exist in crystals, as well as in the liquid form. The accuracy of various force fields applied to study the properties shows that DMNA has the capability of undergoing an inversion about the amine nitrogen, as it lacks a planar geometry.

The strength of the H-bond donation by alcohols is reflected in the carbon-hydrogen bond of the H-C-O-H functional group. The one-bond (super 13)C-(super 1)H spin-spin coupling constant of hexafluoroisopropanol (HFIP) correlates with the strength of the H-bond in various HFIP-amine complexes with a slope of approximately -0.2 Hz in (super 1)J(sub CH) per approximately 1 kJ mol(super -1) increase in the H-bond enthalpy.

The application of the iron(II) complexes of a series of N-acylated dipyridin-2-ylmethylamine ligands (R-DPAH) for the olefins cis-hydroxylation is explained. The complete processes involved in the [Fe.sup.II]/[Fe.sup.IV] catalytic cycle are also analyzed.

One-pot synthesis of 2-aminobenzoxazoles by using commercially available tetramethyl orthocarbonate or 1,1-dichlorodiphenoxymethane, an amine, and an optionally substituted 2-aminophenol is described. The scope of the reactions conducted under mild conditions which provided 2-aminobenzoxazoles in modest to excellent yields was examined by using a variety of amines and substituted 2-aminophenols.