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Ab initio/GIAO-CCSD(T) method is used to study the [.sup.13.C] NMR chemical shifts of bicyclic and related strained olefins. The results show that the relative energies of the various conformers of ethylene correlate very well with the [.sup.13.C] NMR chemical shifts, reflecting the linear dependence of the [.sup.13.C] NMR chemical shifts with the internal strain of the molecules.

Transient UV absorption spectra and kinetics of the CH2I radical in the gas phase are investigated at 313 K. The spectra are found to be a mixture of hot and cold CH2I radicals and parent CH2I2 in the early time range up to a few microseconds.

A systematic characterization of methylene-bridged fluorene oligomers constructed of two, four, six, and eight aromatic rings using time-dependent density functional theory (TDDFT), the ab initio approximate coupled-cluster singles and doubles method, and semiempirical spectroscopic Zerner's intermediate neglect of differential overlap method is reported. Optimized geometries are obtained not only for the electronic ground state but also for the first electronically excited state.

The effects of the linear energy transfer (LET) on the radiation chemical yields of several radiation-induced modifications for alkynes, allenes, alkenes, benzene, and disubstituted benzenes are studied. The results showed that benzene remains in the film and is efficiently formed even for electron irradiations and the relative importance of benzene and disubstituted benzenes is high at low LET and decreases with LET.

The unprecedented N-C coupling of the NO ligand attended by concurrent vinylic C-H activation to form nitrosovinyl derivates is described. The studies have shown that the resulting nitroso-alkene complexes are chemically versatile and valuable species.

Simple and efficient 3-exo-dig cyclizations of propagylic halides possessing a suitably placed active methine are described. Vinylidene cyclopropanes (VCPs) are prepared from electron-rich alkenes by using carbenes derived from propargylic halides and are used as valuable intermediates in organic synthesis.

The NMR spectroscopic characterization of the reaction pathway of the phosphonium alkylidenes with ethylene in the presence of olefin substrate which yields intermediate relevant to olefin metathesis catalytic cycles is reported. The findings provide insight into the structure and the ring closing metathesis catalysis of ruthenacyclobutanes.

The synthesis and characterization of the ferric azido complex and detailed mass spectrometric and theoretical studies of its fragmentation is reported. The findings from the studies provide insight into the free, high-valent iron nitride formed upon oxidative loss of dinitrogen from the azido ligand in the dication [Fe([N.sub.3])].sup.2+] reaction.

The development of a ruthenium-based catalyzed olefin cross-methathesis reaction involving 2- and 4-vinyl-functionalized oxazoles is reported. The method provides new pathway for the synthesis of a biologically active natural products.

The wavelength-dispersed time-resolved transient absorption measurements of [S.sub.1] cis-stilbene in a nonpolar solvent as well as numerical simulation based on the linear response theory is reported. The results offer insight into significance of the non-Condon effect in spectroscopy involving highly excited electronic states.

The development of a ligand-controlled system for the biomimetic cation-olefin cascade cyclization that utilizes trityl cation as catalysts is discussed.

The reduction of the corresponding enol triflates which was used as an effective method to transform both linear and [alpha]-branched aldehydes into terminal olefins is described.

The study explains the effects of the addition of the phenoxathiin cation radical ([PO.sup.+]) to different acyclic alkenes and nonconjugated dienes in acetonitrile solution (MeCN). The reaction has been found to be very useful for the synthesis of (E)- and (Z)-(10-phenoxathiiniumyl)alkenes and (E)- and (Z)-(10-phenoxathiiniumyl)dienes on basic alumina.

The silica supported 2.5-dimethylpyrrolyl family of silica supported Mo imido alkylidine complexes constituted the most efficient d superscript o olefin metathesis which can be prepared in two steps from the readily available triflate derivatives. Preliminary account shows that having methyl substituents on the pyrrolyl ligand in position 2 and 5 improve the stability of the system and that tuning the imido substituents can increase the activity of the catalyst.

A study describes the efficient formation of single-isomer, differentially halogenated alkenes and alkanes that are generated by treatment of the appropriate alkyne or alkene with tetrabutylammonium iodide in refluxing dichloroethane. Exposure of a wide variety of alkynes to [Bu.sub.4]NI in refluxing dichloroethane gave single-isomer E-[beta]-chloro-[alpha]-iodo-[alpha],[beta]-unsaturated ester products every time.

The [super 19]F magic angle spinning (MAS) and [super 1]H-->[super 19]F cross polarization (CP)/MAS NMR spectroscopy are used to investigate the molecular structure and dynamics of novel inclusion compounds (ICs) consisting of n-perfluoroalkane (PFA) guests and [beta]-cyclodextrin ([beta]-CD) host (PFA/[beta]-CD). The results have indicated that the effective intramolecular spin diffusion occurs within a PFA molecule included in [beta]-CD.

The synthesis, spectroscopy, and structural characterization of iron-alkyne and -alkene complexes of the type [L.sup.Me]Fe(ligand) [[L.sup.Me]= bulky [beta]-diketaminate, ligand= HCCPh, EtCCEt, C[H.sub.2]CHPh, EtCHCHEt, HCC[p-[C.sub.6][H.sub.4]OC[H.sub.3]], HCC[p-[C.usb.6][H.sub.4]C[F.sub.3]]]. The binding affinity toward the low-coordinate Fe follows the trend HCCPh> EtCCEt> C[H.sub.2]CHPh> EtCHCHEt~ PP[h.sub.3]> benzene >> [N.sub.2].

A report on a finding that acyclic diene metathesis (ADMET)(super 4) of hexa-peri-hexabenzocoronene (HBC) amphiphile results in the spontaneous formation of graphitic nanotubes with a cross-linked surface is presented. The cross-linked graphitic nanotubes have chemically accessible olefin functionalities on the surface and can, therefore be hybridized with a variety of substances with different functions.

The use of Acr(super +)-Mes as an electron-transfer photocatlyst in the presence of O2 provides a good methodology to produce radical cations of electron donors of anthracenes and olefins and O2(super .-). They combine together to yield the oxygenated products selectively preparative scale.

IR studies indicate that Cu(super +) ions in zeolites CuX, CuY, and CuZSM-5 could activate C=C bonds in alkenes (ethene, propene,. but 1-ene, and cis-but-2-ene). The activation of alkene activation by Cu(super +) in zeolites is similar as in NO activation.

The first example of a catalticenentioselective diboration reaction, which operates on simple alkene subrates, is described. The intial experiments aimed at converting these compounds to optically active synthetic building blocks are described.

A novel method for probing the mechanism of silica surface functionalization with a wide class of organic molecules is presented. This method using high-sensitivity infrared absorption spectroscopy on well-defined surfaces makes it possible to identify unambiguously the reactants and products attached at the surface at all stages of the process.