Synlett 2012(3): 438-442  
DOI: 10.1055/s-0031-1290312
LETTER
© Georg Thieme Verlag Stuttgart ˙ New York

Palladium-Catalyzed Ring Opening of Aminocyclopropyl Ugi Adducts

Aurélie Dos Santos, Laurent El Kaïm*, Laurence Grimaud*, Romain Ramozzi
Laboratoire DCSO ENSTA-Polytechnique-CNRS, UMR 7652, Ecole Nationale Supérieure de Techniques Avancées, 32 Bd Victor, 75739 Paris Cedex 15, France
Fax: +33(1)45528322; e-Mail: laurent.elkaim@ensta.fr; e-Mail: grimaud@dcso.polytechnique.fr;
Further Information

Publication History

Received 14 November 2011
Publication Date:
19 January 2012 (online)

Abstract

The ring opening of aminocyclopropanes triggered by activation with an intramolecular arylpalladium(II) iodide complex is an interesting strategy for the synthesis of nitrogen heterocycles and a valuable Ugi postcondensation-type transformation. Six- and seven-membered-ring cyclic enamines may be obtained.

10

The regioselectivity observed with aryl-substituted amino-cyclopropanes may be explained by a productive interaction of the aryl-Pd(II)I intermediate through the less hindered approach of the cyclopropyl ring. Further insights into the potential electronic effects of the aryl moiety should be addressed by comparison with alkyl-substituted cyclo-propanes.