經由有機催化連鎖1,6/Acetalization/Oxa-Michael加成反應合成三環苯併吡喃酮架構

Abstract

本文利用有機小分子進行有機不對稱三階連鎖反應，得以發展高度官能基非鏡像選擇性的三環苯併吡喃結構。本實驗室利用肉桂醛結合苯磺醯胺與1,3-雙酮所衍生之起始物，利用20 mol% 的碳酸銫，進行1,6/縮醛/1,4加成三階連鎖反應，得到多取代的三環苯並吡喃結構，同時建構四個光學立體中心，有著優異的產率 ( 高達99% ) 及非鏡像選擇性 ( 高達 > 20:1 ) 。此外，也經由單晶繞射X-ray確認產物結構之相對立體組態。

In this paper, organocascade triple reaction that catalyzed by small organic molecules have been developed and successfully accessed to the highly functional diastereoselective tricyclic chromane.The reaction between that cinnamaldehyde combine with phenylsulfonamide and 1,3-dione skeleton and caesium carbonate via 1,6-/acetalization/1,4- addition triple cascade reaction to generate highly functionalized tricyclic and construct four stereocenters in simultaneously. The tricyclic products have been obtained good yields ( up to 99% ) and excellent diastereoselectivities ( up to > 20:1 dr ). The relatived configuration of the cyclized product was determined by the single crystal X-ray analysis.