Enantioselective [3 + 3] Annulation–Deoxalation Strategy for Rapid Access to δ-Oxoesters via N-Heterocyclic Carbene Catalysis
作者:Izabela Barańska、Liliana Dobrzańska、Zbigniew Rafiński
DOI:10.1021/acs.orglett.3c04397
日期:2024.2.16
unprecedented stereoselective synthetic approach to δ-oxoesters derivatives from readily available starting materials has been developed. This method, catalyzed by N-heterocyclic carbene, involves an annulation–deoxalation reaction of alkynyl aldehydes with 2,4-diketoesters and proceeds via the chiral α,β-unsaturated acylazolium intermediates. The annulation includes the in situ formation of dihydropyranones
开发了一种新的、前所未有的立体选择性合成方法,从容易获得的起始材料中合成 δ-氧代酯衍生物。该方法由 N-杂环卡宾催化,涉及炔醛与 2,4-二酮酯的环化-脱草反应,并通过手性 α,β-不饱和酰唑鎓中间体进行。成环包括原位形成二氢吡喃酮,二氢吡喃酮在路易斯酸活化下进行开环甲醇分解,然后进行脱草作用,以中等至良好的收率得到手性 1,5-酮酯。