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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 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 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.

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.

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.