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The importance of the dynamics of equilibrium fluctuations between most stable conformers in the control of the reaction mechanism is discussed. The studies have shown that the nucleophilic attack in 1-acetoxy-2-naphthoic acid (1AC2NA) is promoted by allowing the most stable conformers to equilibrate only through rotation in a direction that has intercepted the reaction coordinate and a general base-catalyzed water attack in 3-acetoxy-2-naphthoic acid (3AC2NA) is favored by favoring equilibrium though rotation that has allowed inclusion of a water molecule in a proper position for reaction.

A series of hybrid organic-inorganic [2]rotaxanes is prepared and characterized. The X-ray crystal structures of different [2]rotaxanes, a pseudorotaxane, and a two-station molecular shuttle has shown two distinct types of intercomponent hydrogen bond motifs between the ammonium groups of the organic thread and the fluoride groups of the inorganic ring. .

Time-resolved spectroscopy is used for comparing the photoinitiated charge separation (CS) and recombination (CR) in a series of donor-bridge-acceptor (D-B-A) molecules with cross-conjugated, linearly conjugated and saturated bridges. Molecular conductance calculations on the bridges have shown that cross-conjugation has resulted in quantum interference effects that have altered the through-bridge donor-acceptor electronic coupling as a function of charge injection energy.

[pi]-Conjugated disilenes with 2-naphthyl or 2-fluorenyl groups on the silicon atoms are prepared as air-stable emissive red solid by using the bulky 1,1,3,3,5,5,7,7-octaethyl-s-hydrindacen-4-yl (Eind) groups. The strong [pi]-[pi]* absorptions and distinct emission at room temperature are observed due to the major contribution of the 3[p.sub.[pi]]*(Si-Si)-2[p.sub.[pi]]*(carbon [pi]-electron system) conjugation.

Density functional theory calculations and molecular mechanics simulations are used for estimating the strength of the nonlocal electron-vibration couplings in oligoacene crystals as a function of molecular size from naphthalene through pentacene. The studies have shown that the amount of relaxation energy associated with nonlocal electron-phonon coupling has decreased as the size of the molecule has increased.

A novel naphthoquinoid singlet biradical stabilized by phenalenyl rings is prepared by a multistep procedure and is examined in terms of covalent bonding interactions. The optical behavior and the magnetic susceptibility measurements have shown that the intermolecular covalent bonding interaction in the 1D chain of naphthoquinoid singlet biradical is greater in strength than the intramolecular one, despite the fact that a fully conjugated Kekule structure can be drawn for naphthoquinoid singlet biradical.

A room temperature reaction between 1,8-Bis(dimethylamino)naphthalene (' Proton Sponge' ) and bromomaleic anhydride to generate 3-(4,5-bis(dimethylamino)napthalen-1-yl)furan-2,5-dione (4-maleicanhydridoproton sponge or 'MAPS') is described. The property of MAPS to lose color upon protonation in solution and change color on reversal indicated the ability of MAPS to act as a colorimetric version of a proton sponge.

The photomechanical effect of a rectangular plate two-component cocrystal composed of a photochromic diarylethene derivative, 1,2-bis(2-methyl-5-(1-naphthyl)-3-thienyl)perfluorocyclopentene (1o), and perfluoronaphthalene (FN) is examined. The crystal of 1o.FN has displayed reversible bending motion upon alternate irradiation with ultraviolet (UV) and visible light, where the reversible bending motion is repeated over 250 times.

The asymmetric total synthesis of nonracemic korupensamine B is described. It has included a newly designed and highly trans-diastereoselective route to the tetrahydroisoquinoline ring and an unprecedented atropdiastereoselective Suzuki-Miyuara coupling for constructing fully fashioned naphthylisoquinoline framework that invokes [pi] stacking as a possible source of stereocontrol.

Highly enantioselective aerobic oxidative cross-coupling of 2-naphthols with broad substrate scope is achieved by using iron(salan) complex as the catalyst. The scope of the cross-coupling reaction is shown to be different from that of the homocoupling reaction under the same reaction conditions.

The 3,5-dinitrobenzoyl-derived 1-naphthylethyl amide is shown to be a good CSA for NMR analysis of protected amines. The analysis has shown that the 3,5-dinitrobenzoyl-derived 1-naphthylethyl amide has formed a chiral cleft that can selectively bind one enantiomer of a substrate through hydrogen bonding, [pi]-[pi] stacking and CH/[pi] interactions.

Naphthyl-bridged bis([beta]-cyclodextrin) is prepared by via ' click chemistry' and its self-assembly behavior is analyzed. The results have shown that the coordination of [Hg.sup.2+] with triazole rings in naphthyl-bridged bis([beta]-cyclodextrin) has induced the naphthyl moiety to move from being a self-included complex to the formation of nanoparticles through intermolecular self-aggregation.

The introduction of a nitrogen atom at one of the acetylenic termini of 10-, 11-, 12-, and 13-membered benzannulated cyclic enediynes has resulted in the complete suppression of the conventional radical Bergman reaction in favor of a polar cycloaromatization. The latter reaction is catalyzed by acids and has proceeded by initial protonation of an ynamide fragment, where the resulting ketenimmonium cation has cyclized to produce naphthyl cation, which has reacted with nucleophiles or undergoes Friedel-Crafts addition to aromatic compounds.

High-level quantum chemical calculations are performed on the two epimeric pairs of complexes 4.2 and 6.2 obtained by lithiation of cinnamyl carbamate and 1-naphthyl derivative in the presence of BOX ligands (S,S)- and (R,R)-2. The studies have shown that in the case of configurationally labile complexes and a dynamic thermodynamic resolution one of both epimers is energetically favored and the quantum chemical computations have allowed the prediction of the enantiomeric excess

Fumaquinone, a novel prenylated naphthoquinone antibiotic, is prepared from ethyl acetoacetate in three steps. The major step of the synthesis is the construction of the naphthoquinone skeleton by a regioselective Diels-Alder reaction between a 2-alkyl 1,3-bis(trimethylsilyloxy)-1,3-diene derivative and a bromoquinone.

The reduction of the steric interaction between the upper-half and the lower-half of a light-driven rotary molecular motor by decreasing the size of the aromatic moiety in the upper-half from naphthalene to a benzothiophene has resulted in a much faster rotation.

The new asymmetric catalytic Strecker reaction of achiral N-phosphonyl imines is described and excellent enantioselectivity are achieved by using primary free natural amino acids as catalysts and [Et.sub.2]AlCN as nucleophile. The studies have presented the novel use of nonvolatile and inexpensive [Et.sub.2]AlCN in asymmetric catalysis and the N-phosphonyl protecting group has enabled simple product purification to be achieved by washing the crude products with hexane.

First-principles calculation of Np[TM.sub.2] (Np = naphthalene, TM = V, Mn, Ti, Nb) sandwich nanowires has shown that the magnetic ordering in the Np[V.sub.2] nanowire can be adjusted by changing its charge state. The carrier-tunable magnetic ordering is unique to the Np[V.sub.2] nanowire and the bonding between the two nearest-neighbor metal atoms has played a major role in controlling the magnetic coupling of charge-neutral Np[TM.sub.2] nanowires.

The synthesis and spectroscopic characterization of a naphthalene-4,5-dicarboximide-1,8-dithiolate diiron complex [NMI-[Fe.sub.2][S.sub.2][(CO).sub.6]] and a covalently linked, fixed-distance zinc 5,10,15-tri-n-pentyl-20-phenylporphyrin-NMI-[Fe.sub.2][S.sub.2][(CO).sub.6] donor-acceptor dyad is reported. Photoexcitation of the disulfide precursor to donor-acceptor dyad in both toluene and C[H.sub.2][Cl.sub.2] which produced only the singlet and triplet excited states of the Zn porphyrin favored electron transfer only in the presence of the diiron complex and photoexcitation of dyad in the presence of trifluoroacetic acid is shown to generate [H.sub.2].

Naphthalene diimide-neomycin and anthraquinone-neomycin conjugates were synthesized and utilized along with pre-synthesized pyrene-neomycin BQQ-neomycin to perform thermodynamic studies on the interactions between intercalator-neomycin conjugates and a DNA polynucleotide triplex [poly(dA)*2poly(dT)]. The results provide insight into the binding affinity of intercalator-neomycin conjugates for poly(dA)*2poly(dT) which increases as a function of the surface area of the intercalator moiety.

The preparation of azulenocyanine with four azulene units fused to a tetraazaporphyrin skeleton from 1,3-di-tert-butyl-5,6-dicyanoazulene is reported. The obtained azulenocyanine which is a structural isomer of naphthalocyanine represents a new type of oxidation-stable near-IR dye.

The water-soluble, self-assembled, tetrahedral assembly [k.sub.12][Ga.sub.4][L.sub.6] (L = 1,5-biscatecholamidenaphthalene) has catalyzed the Nazarov cyclization of 1,3-pentadienols with very high levels of efficiency. The unprecedented rate increase is ascribed to both the stabilization of protonated reaction intermediates and the effect of constrictive binding on the bound guest.

The first oriented multicolored antiparallel redox gradients (OMARG-SHJs) with two-component redox gradients are described in both the electron- and hole-transporting pathways. The presence of both gradients is essential for achieving photoinduced charge separation over very long distances.

The photochemistry of 6,6'ibromo-BINOL (BINOL = 2,2'ihydroxy-1,1'binaphthyl) under mild basic conditions and its methyl and triisopropylsilyl ethers is examined in aqueous acetonitrile through product distribution analysis and laser flash photolysis. Photoreactivity has provided a metal and protecting group free synthetic protocol toward mono- and disubstituted 6-aryl/alkyl BINOLs, since the BINOL chirality is preserved in the photoactivation process.

A modular synthetic approach to 2-aza[6]helicene from synthesis of 2,14-diaza[6]helicene is reported. The method involves the assembly of key hetero biphenylnaphthalenes from functionalized building blocks and metal-catalyzed cycloisomerization.

A versatile synthesis of core-perfluoroalkylated perylene diimides (PDIs) and naphthalene diimides (NDIs) was developed by a strategy featuring perfluoroalkylation of the highly soluble intermediates and their further efficient transformations to target compounds. The Solubility, electrochemistry, and optical properties of the obtained core-perfluoroalkylated PDIs and NDIs are also discussed.

The synthesis and characterization of a series of photochromic ruthenium sulfoxide complexes of the form [[Ru[(bpy).sub.2](OSOR)].sup.+] (bpy = 2,2'-bipyridine and OSOR = 2-(benzylsulfinyl)benzoate (OSOBn), 2-(naphthalene-2-yl-methylsulfinyl)-benzoate (OSONap) or 2-(pentafluorophenylmethanesulfinyl)benzoate (OSOBn[F.sub.5])) are described. The excited state distortion is attributed to low frequency metal-ligand and S[double bond]O vibrational modes, which are involved in the isomerization pathway.

The dearomatization reaction of benzylic chlorides, chloromethylnaphthalenes, and naphthalene allyl chlorides with allenyltributyltin was performed in presence of Pd[(P[Ph.sub.3]).sub.4] catalyst at room temperature to yield the corresponding propargylated and/or allenylated dearomatization products. The reactions provide a new and efficient method for the synthesis of propargylic and allenic carbocycles.