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A satellite-selective 1D-TOCSY method is developed for measuring long-range heteronuclear coupling constants between proton and proton bearing carbons. The comparison of two 1D-TOCSY spectra generated by selective inversion of each [super 13]C satellite of a certain proton signal, Hi, has helped in measuring the long-range heteronuclear couplings between protons of the same spin system as Hi and the carbon bonded to Hi.

The reaction of [[Zn(II)[[[H.sub.2]O].sub.6]].sup.2+] with a minimal, unstructured, tetracysteine 16-mer peptide, GGG is described to elucidate the thermodynamic contribution of a Zn(II)-[(S.Cys).sub.4] site toward metalloprotein stability relevant to classic structural Zn(II) sites. It is demonstrated that the entropy driven binding of Zn(II) reflects the proton dependent chemical speciation of the Zn(II)-[(S.Cys).sub.4] peptide complex.

Large inert, weakly basic carborane anions of the icosahedral type CHB11R5X6-(R=H, Me; X= Cl, Br) allow ready isolation and structural characterization of discrete salts of the solvated proton, [H(solvent)(sub x)][CHB11R5X6], (solvent = common O-atom donor). It contrasts with C-protonation of arene solvents where all the evidence to date points toward mono-solvation of protons in sigma-complexed arenium ions, H(arene(super +45,58).

A combination of [super 1]H and [super 183]W NMR evidence, elemental analysis, acid titration measurements, and H/D isotopomer assignments has established that in nonaqueous media the internal cryptand cavity of [alpha]-[[([H.sub.2])[W.sub.12][O.sub.40]].sup.6-] reversibly accommodates only one more proton to form [alpha]-[Q.sub.5]-[([H.sub.3])[W.sub.12][O.sub.40]]. The results have shown that the transformation is instantaneous by [super 1]H NMR, whereas the reverse process is slow.

The enolization of phenylacetylpyrazine (PzCOC[H.sub.2]Ph) catalyzed by acid, base and metal ions in aqueous solution has shown that metal ions are more effective catalysts that protons. The difference from phenacylpyridine is attributed to the differences in thermodynamic driving force arising from stronger binding of the proton to the more basic pyridine than pyrazine nitrogen atom in both the reactant keto tautomer and in the enaminone or zwitterion product of the rate-determining step of the enolization.

Different multistate generalizations of a two-state (EVB) model for proton hopping between water molecules are used for analyzing the proton transfer (PT) mechanism in liquid water. The transition in real time is monitored, which has shown how the average structure is converted to a distorted [H.sub.5][O.sub.2.sup.+] cation constituting the transitional complex for proton hopping between water molecules.

Green procedure is used to create solvent-free alternatives for conventional Wittig reactions, which are widely used to install a double bond in a highly selective manner. Solvent-free reactions reduce health and environmental risks and provide a basis for an inquiry-based discussion of the stereochemistry of the Wittig reaction and the factors influencing the chemical shifts of alkenyl protons.

A novel class of imidazole-based excited-state intramolecular proton-transfer (ESIPT) materials, that is hydroxy-substituted tetraphenylimidazole (HPI) and its derivative HPI-Ac, which formed large single crystals exhibiting intense blue fluorescence and amplified spontaneous emission (ASE) is synthesized. Fluorescence spectral narrowing and efficient ASE are observed in the HPI-Ac single crystal even at low excitation levels attributed to the intrinsic four-level ESIPT photocycle.

The binding position and the electronic properties of acidic proton in anhydrous dodecatungstophosphoric acid, H3PW12O40 are studied by means of (super 1)H, (super 31)P spin, echo double resonance (SEDOR) NMR techniques. (super 1)H broad line NMR spectrum showed a bell-type resonance line shape with 4.7 kHz line width and magic angle sample spinning (MAS) NMR spectrum has a single resonance peak, suggesting that the hetero-polyanion PW12O40(super 3-) provides a single site to the acidic proton.