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Anion-? interactions influence pK(a) values.

ABSTRACT: Five 8-(4-R-phenyl)-1-naphthol derivatives were prepared by PdCl(2)-catalysed electrophilic aromatic substitution. The pK(a)' values for these 1,8-disubstituted arene naphthols have been measured in acetonitrile/water (R = NO(2), 8.42; R = Cl, 8.52; R = H, 8.56; R = Me 8.68; and R = OMe, 8.71) and indicate a correlation with the electronic nature of the arene substituent, as determined through LFER analysis. Contributions to the relative pK(a)' values have been interpreted, using M06-2X DFT calculations, as consisting of two components: A small contribution from initial OH-? bonding in the starting materials and a larger contribution from anion-? interactions in the products. Such effects have implications for a range of other systems.

SUBMITTER: Cadman CJ

PROVIDER: S-EPMC3079108 | biostudies-literature | 2011 Mar

REPOSITORIES: biostudies-literature

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Anion-π interactions influence pK(a) values.

Cadman Christopher J CJ Croft Anna K AK

Beilstein journal of organic chemistry 20110317

Five 8-(4-R-phenyl)-1-naphthol derivatives were prepared by PdCl(2)-catalysed electrophilic aromatic substitution. The pK(a)' values for these 1,8-disubstituted arene naphthols have been measured in acetonitrile/water (R = NO(2), 8.42; R = Cl, 8.52; R = H, 8.56; R = Me 8.68; and R = OMe, 8.71) and indicate a correlation with the electronic nature of the arene substituent, as determined through LFER analysis. Contributions to the relative pK(a)' values have been interpreted, using M06-2X DFT calc ...[more]

PMID: 21512592

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