Synfacts 2009(7): 0718-0718  
DOI: 10.1055/s-0029-1217384
Synthesis of Heterocycles
© Georg Thieme Verlag Stuttgart ˙ New York

Titanium-Catalyzed Intermolecular Hydroamination Route to Pyrroles

Contributor(s): Victor Snieckus, Cédric Schneider
L. Ackermann*, R. Sandmann, L. T. Kaspar
Georg-August-Universität, Göttingen, Germany
Further Information

Publication History

Publication Date:
22 June 2009 (online)


Based on previous results (L. Ackermann Synlett 2007, 507) two methodologies have been developed for the regioselective preparation of fully substituted pyrroles via titanium-catalyzed intermolecular hydroamination of a dia­stereoisomeric mixture of chloroenynes 2. This is the first report of such a pyrrole synthesis using a mixture of chloroenynes (E/Z)-2 for which an expected mechanism has been proposed. However, since derivatives 2 are often tedious to prepare, the use of the easily prepared α-haloalkynols 1 is an advantage of this method. The final pentasubstituted pyrroles are obtained via electrophilic aromatic substitution reactions within a one-pot protocol.