Original scientific paper

Extended π-Participation in Biomimetic Cyclization of Squalene Derivatives

Stanko Borčić ; Department of Chemistry, Faculty of Pharmacy and Biochemistry, University of Zagreb, Ante Kovačića 1, 10000 Zagreb, Croatia
Krešìmir Humski ; Department of Chemistry, Faculty of Pharmacy and Biochemistry, University of Zagreb, Ante Kovačića 1, 10000 Zagreb, Croatia
Olga Kronja ; Department of Chemistry, Faculty of Pharmacy and Biochemistry, University of Zagreb, Ante Kovačića 1, 10000 Zagreb, Croatia
Ivica Malnar ; Department of Chemistry, Faculty of Pharmacy and Biochemistry, University of Zagreb, Ante Kovačića 1, 10000 Zagreb, Croatia

Abstract

Chlorides 4 (1-aryl-1-chloro-5,9,14,18,22-pentamethyl-5,9,13,17,21- tricosapentaenes) with various phenyl substituents were prepared, and solvolysis rates were measured in aqueous ethanol Op = 95% and 80%) and in aqueous 2,2,2-trifluoroethanol (w = 97%). Hammett p+ values obtained are -1.86, —1.81 and —1.56, respectively, suggesting concerted cyclization of at least two double bonds in the rate determining step.

Keywords

Hrčak ID:

135974

URI

https://hrcak.srce.hr/135974

Publication date:

2.12.1996.

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