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arXiv · 1408.5161

On the role of interfacial hydrogen bonds in "on-water" catalysis

Kristof Karhan·Rustam Z. Khaliullin·Thomas D. Kühne
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Abstract

Numerous experiments have demonstrated that many classes of organic reactions exhibit increased reaction rates when performed in heterogeneous water emulsions. Despite enormous practical importance of the observed "on-water" catalytic effect and several mechanistic studies, its microscopic origins remains unclear. In this work, the second generation Car-Parrinello molecular dynamics method is extended to self-consistent charge density-functional based tight-binding in order to study "on-water" catalysis of the Diels-Alder reaction between dimethyl azodicarboxylate and quadricyclane. We find that the stabilization of the transition state by dangling hydrogen bonds exposed at the aqueous interfaces plays a significantly smaller role in "on-water" catalysis than has been suggested previously.

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Kristof Karhan, Rustam Z. Khaliullin, Thomas D. Kühne. 2014-08-21. On the role of interfacial hydrogen bonds in "on-water" catalysis. https://doi.org/10.1063/1.4902537

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