Back to Search
Start Over
Hydrogen-bonded channel-dependent mechanism of long-range proton transfer in the excited-state tautomerization of 7-hydroxyquinoline: a theoretical study.
- Source :
-
Theoretical Chemistry Accounts: Theory, Computation, & Modeling . Feb2017, Vol. 136 Issue 2, p1-13. 13p. - Publication Year :
- 2017
-
Abstract
- The first excited-state proton transfer (ESPT) in 7-hydroxyquinoline (7HQ) mediated by water and methanol molecules in a nonpolar solution was studied by quantum mechanical calculations. The multiple proton transfer through a hydrogen-bonded channel consisting of two or three hydroxyl molecules occurs in a concerted and asynchronous pathway. When the H-bonded channel molecules are water or methanol, proton transfer takes place in a solvolytic or protolytic fashion, respectively. The barrier height of the ESPT depends on the basicity of the H-bonded channel. The predicted barrier height is 2.97 kcal/mol lower with two CHOH than with two HO since monomeric methanol is more basic than monomeric water in heptane and DPE. The ESPT barrier heights are 3-4 kcal/mol lower with three H-bonded molecules than with two. The rate constants and KIEs for the ESPT of 7HQ-(ROH) (ROH = HO, CHOH) were calculated and compared to the experimental values. [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 1432881X
- Volume :
- 136
- Issue :
- 2
- Database :
- Academic Search Index
- Journal :
- Theoretical Chemistry Accounts: Theory, Computation, & Modeling
- Publication Type :
- Academic Journal
- Accession number :
- 121331918
- Full Text :
- https://doi.org/10.1007/s00214-017-2055-5