Synthesis 2010(13): 2129-2138  
DOI: 10.1055/s-0029-1218787
PAPER
© Georg Thieme Verlag Stuttgart ˙ New York

A Route to Alkenyl-Substituted 4-Hydroxypyridine and Pyrimidine Derivatives via Three-Component Access to β-Alkoxy-β-ketoenamides

Mrinal K. Bera, Hans-Ulrich Reissig*
Institut für Chemie und Biochemie, Freie Universität Berlin, Takustr. 3, 14195 Berlin, Germany
Fax: +49(30)83855367; e-Mail: hans.reissig@chemie.fu-berlin.de;
Further Information

Publication History

Received 29 March 2010
Publication Date:
20 May 2010 (online)

Abstract

β-Alkoxy-β-ketoenamides with an alkenylated side arm were prepared by three-component reaction of lithiated methoxy­allene, nitriles, and α,β-unsaturated carboxylic acids. Their subsequent treatment with trimethylsilyl triflate and base provided 6-alkenyl-4-hydroxypyridine derivatives that were converted into the corresponding nonaflates. Alternatively, condensation of β-alkoxy-β-ketoenamides with an ammonium salt led to the smooth formation of alkenyl-substituted pyrimidine derivatives. The alkenyl group in pyridine or pyrimidine derivatives allows a wide scope of functional group modification. Moreover, the pyridin-4-yl nona­flates are excellent candidates for palladium-catalyzed coupling reactions­ and the 6-methyl group of the pyrimidine derivatives could also be employed for the introduction of functional groups and subsequent reactions. A variety of highly substituted pyridine and pyrimidine derivatives are available by this modular route to heterocycles.