Proton transfer, hydrogen bonds quantum mechanics

Tapia, O. Quantum mechanics and the theory of hydrogen bond and proton transfer. Beyond a Bom-Oppenheimer description of chemical interconversions, J.Mol.Str.Theochem, 433 (1998) 95-105. 

Hydration has also been recorded by Fischer and Wan , who reported that the phenol derivatives 18, 19 and 20 undergo addition of water to the double bond when they are irradiated in acetonitrile/water. The study has shown that the proposed mechanism of m-quinonemethide (see later for further discussion of quinonemethides) formation probably involves a solvent-mediated proton transfer of the phenolic hydrogen to the -carbon of the alkene moiety. This must occur with the participation of a so-called water trimer. This yields the zwitterion 21 that is responsible for the formation of the products, e.g. 22 from 18. The reactions are efficient with quantum yield values of 0.1-0.24. 

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