Diphenoquinhydrones and Related Hydrogen-Bonded Charge-Transfer Complexes

Abstract

Benzoquinone and hydroquinone cocrystallize to form quinhydrone, a 1:1 complex with a characteristic structure in which the components are positioned by hydrogen bonds and charge-transfer interactions. We have found that analogous diphenoquinhydrones can be made by combining 4,4′-diphenoquinones with the corresponding 4,4′-dihydroxybiphenyls. In addition, mixed diphenoquinhydrones can be assembled from components with different substituents, and mismatched quinhydrones can be made from benzoquinones and dihydroxybiphenyls. In all cases, the components of the resulting structures are linked in alternation by O–H···O hydrogen bonds to form essentially planar chains, which stack to produce layers in which π-donors and π-acceptors are aligned by charge-transfer interactions. Geometric parameters, computational studies, and spectroscopic properties of diphenoquinhydrones show that the key intermolecular interactions are stronger than those in simple quinhydrone analogues. These findings demonstrate that the principles of modular construction underlying the formation of classical quinhydrones can be generalized to produce a broad range of hydrogen-bonded charge-transfer materials in which the components are positioned by design.

Refreshing the Legacy of Rudolf Nietzki: Benzene-1,2,4,5-tetramine and Related Compounds

“…For example, surprisingly little has been done to reveal how molecules of this type are arranged in the crystalline state, despite the likelihood of discovering novel patterns of hydrogen bonding, charge transfer, and other interactions, as found in structures composed of analogous hydroquinones and quinones. 61 To learn more about BTA (1) and its derivatives, we have improved their methods of synthesis, studied their reactions, crystallized selected compounds, and solved their structures by X-ray diffraction. Our results create a foundation for using the compounds in new ways in the future, particularly as components of redox-active materials for storing energy.…”

“…Paradoxically, even though BTA ( 1 ), its oxidized form BTA-H 2 ( 2 ), and related compounds have been available for over a century and are widely used, many fundamental properties have not been studied adequately. For example, surprisingly little has been done to reveal how molecules of this type are arranged in the crystalline state, despite the likelihood of discovering novel patterns of hydrogen bonding, charge transfer, and other interactions, as found in structures composed of analogous hydroquinones and quinones . To learn more about BTA ( 1 ) and its derivatives, we have improved their methods of synthesis, studied their reactions, crystallized selected compounds, and solved their structures by X-ray diffraction.…”

Supramolecular design as a route to high-performing organic electrodes

“…Later, Wuest and coworkers showed how more complex benzoquinone-hydroquinone cocrystals could be generated by synergistic hydrogen bonds between these redox-active units. 53 By exploring several quinonoid compounds, the authors show how the charge-transfer behavior of these materials was related to their H-bonding. These efforts demonstrate how careful tuning of hydrogen bond interactions can be used to control multi-length scale structure and prevent dissolution of organic electrodes.…”