The addition of L-cysteine without blocking amino and carboxyl groups to${\beta},{\beta}$-dinitrostyrene derivatives(11a-e) were investigated. ${\beta},{\beta}$ -Dinitrostyrene derivatives(11a-e) easily undergo addition reactions with L-cysteine to from s-(2,2-dinitro-1-phenylethyl)-L-cysteine(12a), s-[2,2-dinitro-1-(p-methyl)phenylethyl]-L-cysteine (12b), s-[2,2-dinitro-1-(p-methoxy)phenylethyl]-L-cystein e(12c), s-[2,2-dinitro-1-(p-chloro)phenylethyl]-L-cysteine (12d) and s-[2,2-dinitro-1-(p-nitro)phenylethyl]-L-cysteine( 12a), respectively. The structure of adducts were confirmed by means of spectral data, molecular weight measurement and elemental analysis.

The molecular interaction and geometrical optimization of Cr$(CO)_5\;and\;Ni(CO)_3$ units have been studied for phosphinidene complex by means of extended Huckel calculations. The results were compared with those of ab initio calculations and found to be in qualitative agreement. Geometrical optimization of HPCr$(CO)_5\;(1)\;and\;HPNi(CO)_3$ (2) gave the values R = 2.36 ${\AA}$, ${\theta}$ = $111.5^{\circ}$, and ${\phi}$ = $45^{\circ}$for 1, and R = 2.37 ${\AA}$, ${\theta}$= $120^{\circ}$, and ${\phi}$ = $58^{\circ}$for 2. It is found that the low rotational barriers for 1(0.46 kcal $mol^{-1}$) and 2(0.12 kcal $mol^{-1}$) would be accompanied by the free rotation, in spite of the fact that both 1 and 2 adopt staggered conformations.

The molecular interaction of $Mo_2(OR)_4({\mu}-OR)_2$$ unit has been studied for carbonyl and acetylene ligands by means of extended Huckel calculations. We have extended the extended Hckel calculations to unknown apex bridged $Mo_2(OR)_6({\mu}-X)$ complexes (X = $SO_2$H, and Cl) in order to compare the stability of the complexes. In the $C_2H_2$and H apex bridged complexes, one finds a relatively small HOMO-LUMO gap. However, both complexes are stabilized due to Jahn-Teller distortion. The stability of both complexes is comparable to that of $Mo_2(OR)_6(CO)$ complex. The comparisons and predictions in the stability of known and unknown complexes are the subject of this study.

Lithium bonded complexes with $H_2O$ molecule were investigated theoretically by varying the substituent of lithium compound as follows; LiH, LiLi, $LiCH_3,\;LiNH_2$, LiOH, LiF, and LiCl. Some hydrogen bonded complexes with $H_2O$ molecule were also investigated to be compared with lithium bonded analogues. Electron correlation effect on the structures and energies of lithium bond was also investigated through MP2 and MP4 corrections. Unlike hydrogen bond with $H_2O$ molecule, lithium bonded complexes with $H_2O$ molecule were found to be interacting linearly with $H_2O$ molecule. Electron correlation effect was very small for lithium bonded complexes. The lithium bond energies were found to be less affected by the choice of substituent of lithium compound.

The stereochemistry of N-acyliminium cyclizations to form decahydropyrrolo[2,1-a]isoquinolin-3(2H)-ones was studied. Particular attention was paid to the stereocontrol by an acetoxy group present on pyrrolidone ring. Two of the three new chiral centers were formed stereospecifically, and the third was controlled by elimination-hydrogenation sequence.

Kinetics and mechanism of the nucleophilic substitution reactions of phenacyl bromides with anilines in methanol-acetonitrile mixtures at $45.0^{\circ}C$ are reported. The reaction is found to proceed via $S_N2$ process, but the magnitudes of cross interaction constants, ${\rho}_{XY}$, between substituents X in the nucleophile and Y in substrate were unusually small, even after allowing for the fall off due to non-conjugative intervening -CO group in the reactant. As in the other phenacyl derivatives, the resonance shunt phenomenon was invoked to explain the remarkable diminuation of the $|{\rho}_{XY}|$ values.

Cleavage of exo-7-substituted-6,8-dioxabicyclo[3.2.1]octanes with acetyl iodide in the predominance of the trans alkene product. This bicyclic ketal fragmentation methodology is utilized to a formal synthesis of sirenin.

We have investigated the infrared spectra for carbon monoxide chemisorbed on silica supported ruthenium with and without potassium coating within the frequency range of 1800-2200 $cm^{-1}$ at various ruthenium concentrations and CO pressures. For the system without potassium coating, three bands were observed in the infrared spectra when CO was adsorbed on both the reduced and oxidized form of supported ruthenium. However, the relative intensities of these three bands were found to have no interdependence. Therefore, we have assigned each of these bands as arising from the CO stretching vibration for carbon monoxide molecules adsorbed on the Ru sites of different nature. On coating with potassium, the 2030 $cm^{-1}$ band observed for the system without potassium coating was found to suffer red shift by 10-30 $cm^{-1}$ and we conclude that this bathochromic shift is caused by enhancement in the capability of back donation of electrons from the metal atom to the antibonding ${\pi}{\ast}$ orbitals of CO due to the presence of potassium.

Reaction of thianthrene cation radical perchlorate (1) with 1-methyl-4-benzenesulfonylaminobenzene (10) afforded thianthrene (5), N-(4-tolyl)-N-thianthrenylbenzenesulfonamide (14), 1-methyl-3-[N-(4-tolyl)-N-benzenesulfonyl-amino- 4-benzene-sulfonylaminobenzene (16), cis-thianthrene-5,10-dioxide (17), 5-(3'-methyl-6-benzenesulfonylaminobenzene)thian threnium perchlorate (18), and benzenesulfonate. In the meantime, reaction of 1 with 1-ethyl-4-benzenesulfonylaminobenzene (12) afforded 5, 1-ethyl-3-[N-(4-ethylphenyl)-N-benzenesulfonyl]a mino-4-benzenesulfonylaminobenzene (19), 1-benzenesulfonyl-amino-4-[1-(2-benzenesulfonyla mino-5-ethylphenyl)ethyl]benzene (20), and 1-(1-acetamidoethyl)-4-benzenesulfonylaminobenz ene (21). The formations of these products except for 18 and benzenesulfonate could be rationalized by assuming a sulfonamidyl radical as an intermediate.

A mixture of (Z,Z)-3,13-octadecadien-1-yl acetate(1) and its (E,Z)-isomer(2), the sex pheromone of the cherry tree borer, Synanthedon hector Butler was synthesized. (Z)-11-Octadecen-1-al(3) was prepared from 1,10-decandiol. The Wittig reaction the above aldehyde3 with carboethoxymethylenetriphenylphosphorane, or the Wadsworth-Emmons reaction of the above aldehyde3 with the anion of triethylphosphonoacetate gave ethyl (Z,Z)-2,13-octadecadienoate and its (E,Z)-isomer. Deconjugative protonation of ethyl (Z,Z)-2,13-octadecadienoate and its (E,Z)-isomer with potassium hexamethyldisilazide followed by aqueous ammonium chloride work-up afforded stereoselectiv디y ethyl (E,Z)-3,13-octadecadienoate and its (Z,Z)-isomer, respectively, of which stereoselectivity was adjusted to give the product in the required ratio. Exposure of the above deconjugated ester to excess lithium aluminium hydride resulted in formation of the penultimate (Z,Z)-3,13-octadecadien-1-ol and its (E,Z)-isomer. Acetylation of the desired alcohols afford the final products, (Z,Z)-3,13-octadecadien-1-yl acetate(1) and its (E,Z)-isomer(2).

Ab initio calculations are performed for $ArCO_2^+$ and $ArCO_2$. Between the two configurations of $ArCO_2^+$ the orbital interactions and the higher order correlation calculations favor the T-shape, and their interaction energies are calculated to be approximately half the experimental values using 6-31G$^{\ast}$ basis set. In $ArCO_2$, the calculations qualitatively favor the T-structure, which is compatible with the experiment. However, the true interaction energy is obscured since it is within the BSSE limit at this basis set size and the correlation level. Addition of sp type diffuse functions increase the interaction energies by a considerable amount, but the BSSE estimated by CP method are responsible for the significant portion of the difference. The possible equilibrium structure of the $Ar^+-CO_2$ complex, where the charge is localized on Ar, is suggested as having a linear structure. The potential energy surface and the amount of charge transfer are shown to be sensitive to the type and balancing of basis set.

The rates of hydrolysis of N-(benzenesulfonyl) benzimidoyl chlorides (p-H, $p-CH_3,\;p-CH_3,\;p-NO_2\;and m-NO_2$) have been measured by UV spectrometry in 60% methanol-water at $25^{\circ}C$ and a rate equation which can be applied over wide pH range was obtained. Below pH 7.00, the substituent effect on the hydrolysis rate of N-(benzenesulfonyl) benzimidoyl chloride was found to conform to the Hammett ${\sigma}$ constant with ${\rho}$ = -0.91, whereas above pH 9.00, with ${\rho}$ = 0.94. On the basis of the rate equation obtained and the effect of solvent, substituents and salt, the following reaction mechanism were proposed; below pH 7.00, the hydrolysis of N-(benzenesulfonyl) benzimidoyl chloride proceeds by $S_N1$ mechanism, however, above pH 9.00, the hydrolysis is initiated by the attack of the hydroxide ion and in the range of pH 7.00-9.00, these two reactions occur competitively.

Infrared multiphoton decompositions (IRMPD) of $BrCH_2CH_2CH_2CH_2Cl$ were studied by using the pulsed $CO_2$laser. At 0.3 J laser energy the experimentally observed product ratios could be reasonably explained by the RRKM calculation with initial excitation energy of ca. 80 Kcal/mol. The pressure dependence of product yields led us to conclude that the collisional deactivation by the inert gas decreased the yield of low energy dissociation channel more significantly.

7-Dithiocarboxy-3-phenyl-5,6-dihydro imidazo[2,1-b]thiazolium-betaine (2) was prepared by treatment of 3-phenyl-5,6-dihydro imidazo[2,1-b]thiazole (1) with carbon disulfide in acetone at room temperature. On the reaction of 2 with para-substituted phenacyl bromides (4) having the electron withdrawing property by virtue of (+) resonance (R) < (-) inductive (I) or (-) resonance (R), (-) inductive (I) effect, ring transformation product p-substituted-2-[2-[7-(p-substituted benzoyl)-5-thioxo-2,3-dihydro-1H-imidazo[1,2-c] thiazol-1-yl]-2-phenylvinylthio] acetophenone (6) was obtained; however, when R is electron donating grops with (+) resonance (R) > (-) inductive (I) effect the quarternary ammonium salt 7-(p-substituted phenyl) carbonyl methyl-3-phenyl-5,6-dihydro imidazo [2,1-b] thiazolium bromide (8) is formed. The reaction of 2 with unsubstituted-phenacyl bromide (R = H), on the other hand, gives 6a and 8a to the similar ratio, respectively.

Formation of intermolecular charge-transfer complexes between 7,7,8,8-tetracyanoquinodimethane (TCNQ) and two different series of stilbene derivatives has been studied spectroscopically at $25^{\circ}$C in 1,2-dichloroethane. The compounds of Series I include stilbene and derivatives which have fused phenyl rings on one end of the central ethylene structure and a phenyl ring on the other end. The other Series, II, is comprised of stilbenes which have various para substituents on one of the two phenyl rings. The equilibrium constant, $K_c^{AD}$ and the molar extinction coefficient, ${\varepsilon}_{\lambda}^{AD}$, were determined using the Scott equation. The values of the charge-transfer transition frequency, ${\vu}_AD$ and $K_c{AD}$ correlated well respectively with the ionization potentials of the fused rings of Series Ⅰ or of the compounds of Series II and with the values of ${\sigma}_p$, the Hammett constants of the Series II substituents. trans-4-N,N-Dimethylaminostilbene and trans-4-nitrostilbene were found to be able to participate in electron transfer reaction with TCNQ forming the corresponding anion radical, TCNQ$^-$:

The spectral properties of piroxicam in different solvents are similar to those of its skeletal precursor, HMBDC. The maximum absorption and emission wavelengths strongly depend on the hydrogen bonding ability of the solvent, and it is shown that intramolecular hydrogen bonding between the -OH and the ortho carbonyl group of the parent benzothiazine ring plays an important role in the solvent-dependence of their spectroscopic properties. The fluorescence spectra in aprotic nonpolar solvent exhibit abnormally large Stokes-shifted (${\sim}9,000cm^{-1}$) emission bands in contrast to the spectra in water. In ethanol, dual emission bands with two different fractional components of lifetimes have been observed. These results suggest that the abnormally red-shifted emission is attributed to the proton transferred form of an intramolecularly hydrogen-bonded closed conformer.

3-Methoxy-4-cyano-2,9-dioxabicyclo[4.3.0]non-3-e ne (1) was prepared by (4 + 2) cycloaddition reaction of methyl ${\alpha}$-cyanoacrylate with 2,3-dihydrofuran. Compound 1 was ring-open polymerized by cationic catalyst such as boron trifluoride etherate to obtain alternating head-to-head (H-H) copolymer (2) of methyl $\alpha$ -cyanoacrylate and 2,3-dihydrofuran. For comparison, head-to-tail (H-T) copolymer (3) was also prepared by free radical copolymerization of the corresponding monomers. The H-H copolymer exhibited minor differences in its $^1H$-NMR and IR spectra, but in the $^{13}C$-NMR spectra significant differences were observed between the H-H and H-T copolymers. All of the H-H and H-T copolymers were soluble in common solvents and the inherent viscosities were in the range 0.2-0.3 dl/g.

A simple correlation between cross interaction constants ${\rho}_{ij}$ and bond lengths in the transition state was obtained ; it has been shown that ${\rho}_{ij}$ corresponds to force constant of activation, which in turn is related to bond length by Badger's rule involving only universal constants. A satisfactory correlation between 4-31G ab initio calculated values of bond length and force constant for C-X streching in the transition state of the methyl transfer reaction, $X^-\;+\;CH_3X\;=\;XCH_3\;+\;X^-$, indicated that Badger's rule can be extended to bonds in the transition state. Independence of ${\rho}_{ij}$ values from the variable charge transmission of reaction centers has been demonstrated with nearly constant, experimentally determined I${\rho}$XYI values, and hence similar degree of bond formation, for various $S_N2$ reactions.