Metal Triflates-Catalyzed Conjugate Addition of Homochiral Pyrroles to α,β-Unsaturated Esters

Canan Ünaleroglu; Baris Temelli; Ayhan S. Demir

doi:10.1055/s-2004-831195

PAPER

Metal Triflates-Catalyzed Conjugate Addition of Homochiral Pyrroles to α,β-Unsaturated Esters

Canan Ünaleroglu*^a, Baris Temelli^a, Ayhan S. Demir^b
^a Hacettepe University, Department of Chemistry, 06532 Ankara, Turkey
^b Middle East Technical University, Department of Chemistry, 06531 Ankara, Turkey
Fax: +90(312)2992163; e-Mail: canan@hacettepe.edu.tr;

Abstract

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Abstract

The Friedel-Crafts reaction of homochiral pyrrole derivatives with α,β-unsaturated esters catalyzed by metal triflates furnished conjugate addition products. The best yields were obtained by using yttrium triflate and methyl 4-phenyl-2-oxobut-3-enoate (2a). The addition worked regioselectively at C-5 of pyrrole. The diastereoisomers were separated by column chromatography.

Key words

homochiral pyrroles - metal triflates - conjugate addition - Friedel-Crafts reaction - pyrroles

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Referenzen

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