One-pot synthesis of pyrrolidino- and piperidinoquinolinones by three-component aza-Diels–Alder reactions of in situ generated N-arylimines and cyclic enamides
作者:Wenxue Zhang、Yisi Dai、Xuerui Wang、Wei Zhang
DOI:10.1016/j.tetlet.2011.09.021
日期:2011.11
An efficient synthesis of hexahydropyrrolo[3,2-c]quinolin-2-ones and hexahydropyridino[3,2-c]quinolin-2-ones has been developed in moderate to high yields by one-pot two-step aza-Diels-Alder reactions of N-arylimines, formed in situ from anilines and benzaldehydes, with cyclic enamides, formed in situ from 5-hydroxypyrrolidin-2-ones and 6-hydroxypiperidin-2-ones by BF3 center dot OEt2-promoted dehydration in dichloromethane at room temperature. The hexahydropyrrolo[3,2-c]quinolin-2-ones were formed as a single exo-stereoisomer in most cases and hexahydropyridino[3,2-c]quinolin-2-ones were formed as a mixture of exo- and endo-isomers favoring the endo-diastereomer. (C) 2011 Elsevier Ltd. All rights reserved.