Sequential <i>aza</i>-Baylis−Hillman/Ring Closing Metathesis/Aromatization as a Novel Route for the Synthesis of Substituted Pyrroles
作者:Valérie Declerck、Patrice Ribière、Jean Martinez、Frédéric Lamaty
DOI:10.1021/jo048519r
日期:2004.11.1
2-substituted-3-methoxycarbonyl pyrroles has been developed. Diverse SES protected α-methylene β-aminoesters were obtained by a 3-component aza-Baylis−Hillman reaction. Diversity arose from the aryl aldehydes which can be used in this reaction. N-Alkylation with allyl bromide under mild conditions provided the corresponding dienes. These substituted dienes were cyclized by ring closing metathesis at room
已经开发出一种新的途径来制备各种2-取代的3-甲氧基羰基吡咯。通过3-组分氮杂-Baylis-Hillman反应获得了多种SES保护的α-亚甲基β-氨基酯。可以用于该反应的芳基醛引起多样性。在温和条件下用烯丙基溴进行N-烷基化可提供相应的二烯。这些取代的二烯通过在室温下或在用格鲁布斯(Grubbs)II型催化剂进行微波活化下的闭环复分解反应而环化,得到SES保护的吡咯啉中间体。最终的吡咯是通过碱促进的脱氢脱亚磺酰化/芳香化获得的。探索了每个反应的范围。