Original scientific paper

Hydrogen Bonding Properties of Pharmaceuticals. Part 1. 2,3,4,5-Tetraiodo, Tetrabromo and Tetrachloropyrroles as Medium-Strong Proton Donors

Antti Kivinen ; Division of Chemistry, School of Pharmacy, University of Helsinki, Fabianinkatur , SF-00170 Helsinki 17, Finland
Helena Auvinen ; Division of Chemistry, School of Pharmacy, University of Helsinki, Fabianinkatur , SF-00170 Helsinki 17, Finland
Jarmo Huuskonen ; Division of Chemistry, School of Pharmacy, University of Helsinki, Fabianinkatur , SF-00170 Helsinki 17, Finland
Keijo Vakiparta ; Division of Chemistry, School of Pharmacy, University of Helsinki, Fabianinkatur , SF-00170 Helsinki 17, Finland

Abstract

Heteroassociation of 2,3,4,5-tetraiodopyrrole and its bromo and .
chloro analogues with acetone, tetrahydrofuran, pyridine, dimethyl
sulphoxide, and hexamethylphosphorictriamide in carbon tetrachloride
was studied by means of infrared spectroscopy. Values of
the formation constants for 1 : 1 complexes and the ~vNH frequency
shifts of these acid-base pairs are reported. The proton
donor strengths of the halogenated pyrroles were found to be of
the same order of magnitude as that of phenol. In most cases the
structure of the bonded NH stretching absorption is irregular,
containing several maxima and minima. The reasons for this irre·gularity
are discussed.

Keywords

Hrčak ID:

194280

URI

https://hrcak.srce.hr/194280

Publication date:

1.7.1982.

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