Synlett 2010(16): 2425-2428  
DOI: 10.1055/s-0030-1258047
LETTER
© Georg Thieme Verlag Stuttgart ˙ New York

Three-Component Mannich Couplings En Route to Substituted Aminophenol and Benzoxazine Derivatives

Sonia Barrosoa, Ana M. Abreua, Ana C. Araújoa, Ana M. Coelhoa, Nuno Maulide*b, Ana M. Martins*aa Centro de Química Estrutural, Instituto Superior Técnico, Avenida Rovisco Pais, 1049-001 Lisboa, Portugal
e-Mail: ana.martins@ist.utl.pt; Fax: +351(21)8464457;
b Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
e-Mail: maulide@mpi-muelheim.mpg.de;
Further Information

Publication History

Received 21 July 2010
Publication Date:
19 August 2010 (eFirst)

Abstract

The three-component Mannich coupling of phenols, primary amines, and aldehydes was investigated. Unexpectedly, benzoxazine products were obtained in most cases, even in instances where steric hindrance would seem to militate against benzoxazine formation. The stereoselective synthesis of such benzoxazines, their hydrolysis to aminophenol derivatives, and the mechanisms involved are presented and discussed.