Molecular geometry as a source of chemical information. 5. Substituent effect on proton transfer in para-substituted phenol complexes with fluoride--a B3LYP/6-311+G study

Tadeusz M Krygowski; Halina Szatyłowicz; Joanna E Zachara

doi:10.1021/ci049633d

Molecular geometry as a source of chemical information. 5. Substituent effect on proton transfer in para-substituted phenol complexes with fluoride--a B3LYP/6-311+G study

J Chem Inf Model. 2005 May-Jun;45(3):652-6. doi: 10.1021/ci049633d.

Authors

Tadeusz M Krygowski¹, Halina Szatyłowicz, Joanna E Zachara

Affiliation

¹ Department of Chemistry, Warsaw University, Pasteura 1, 02-093 Warsaw, Poland.

PMID: 15921455
DOI: 10.1021/ci049633d

Abstract

The simplified model system [p-X-PhO...H...F](-), where -X are -NO, -NO(2), -CHO, -H, -CH(3), -OCH(3), and -OH, with various O...F distance was used to simulate the wide range of the H-bond strength. Structural changes due to variation of the substituent as well as the H-bond strength are well monitored by the changes in the aromaticity index HOMA and by two empirical measures of the H-bond strength-the (1)H NMR chemical shift of proton involved and the C-O bond length. Changes in H-bonding strengths and the position of proton transfer while shortening the O...F distance are well described by the Hammett equation.