title: A redox active proton transfer and hydrogen-bonding system of tetrathiafulvalene-dicarboxylic acid and pyridine bases.
abstract: Hydrogen bonds are important in supramolecular chemistry and responsible for proton transfer processes. This manuscript reports new hydrogen-bonding systems of redox-active acid-base assemblies consisting of dimethylthio-tetrathiafulvalene dicarboxylic acid (H(2)L) coupled with pyridine (py), 2,2'-bipyridine (2,2'-bpy), and 4,4'-bipyridine (4,4'-bpy). The (1)H NMR chemical shifts of the pyridines and the redox potential shifts of the tetrathiafulvalene moiety indicate that proton-transfer and strong hydrogen-bonding interactions exist between the acid and the bases in aprotic solvents. The results of cyclic voltammetry show a two-step square reaction with a redox and proton transfer coupled mechanism. The nature of the hydrogen bonds was characterized by X-ray single crystal analysis. In contrast to the mono-carboxyl-py system, in this ortho-substituted dicarboxyl-py system one proton of the H(2)L transfers completely from the carboxyl to the py group. The conjugated intramolecular and intermolecular hydrogen bonds are responsible for the proton transfer.
authors.affiliation: Department of Chemistry & Key Laboratory of Organic Synthesis of Jiangsu Province, Soochow University, Suzhou 215123, P. R. China.
authors.forename: Peng
authors.initials: P
authors.lastname: Huo
authors.forename: Jin-Po
authors.initials: JP
authors.lastname: Wang
authors.forename: Ming-Yan
authors.initials: MY
authors.lastname: Shao
authors.forename: Yong-Gang
authors.initials: YG
authors.lastname: Sun
authors.forename: Shu-Fang
authors.initials: SF
authors.lastname: Ji
authors.forename: Qin-Yu
authors.initials: QY
authors.lastname: Zhu
authors.forename: Jie
authors.initials: J
authors.lastname: Dai