2-Pyridones from Cyanoacetamides and Enecarbonyl Compounds: Application to the Synthesis of Nothapodytine B
摘要:
The condensation of an enone or enal with cyanoacetamide derivatives and t-BuOK furnishes either 3-eyano-2-pyridones or 3-unsubstituted-2-pyridones, depending on whether the reaction is carried out in the presence or in the absence Of O-2. In the first case, in situ oxidation of Michael-type intermediates takes place; in the second case, the products result from "decyanidative aromatization" of such intermediates. A one-step synthesis of 3-alkyl-2-pyridones has been devised on the basis of decyanative union of an enone/enal and a 2-alkyleyanoacetamide. The new reaction forms the centerpiece of an unusually concise synthesis of nothapodytine B (mappicine ketone).
Facile palladium-mediated substitution of chlorine in 2-chloroquinolines
作者:Marco A. Ciufolini、James W. Mitchell、Frank Roschangar
DOI:10.1016/0040-4039(96)01937-5
日期:1996.11
Unlike ordinary aryl chlorides, the title hererocycles participate readily in Castro-Stephens, Stille, Suzuki, and carbonylation reactions under the catalytic influence of Pd(0).
A highly efficient one-pot synthesis of 2-chloro-3-substituted quinolines has been developed by tetrabutylammonium chloride-triggered 6-endo cyclization of o-alkynylisocyanobenzenes, which are generated in situ by dehydration of the corresponding N-(2-ethynylphenyl)formamides. (C) 2009 Elsevier Ltd. All rights reserved.