1,3-噁唑烷的結構普遍存在於天然物和醫學藥物中。本研究發展出有效率的合 成路徑,加入不同取代基的γ-羥基-α,β-不飽和酮類30 和3,4-二氫異喹?49 作為起 始物,經由aza-Michael 加成反應和親核反應組成的連鎖反應,在溫和的條件下, 不需要加入任何的催化劑,反應15 分鐘後能夠快速得到各種不同系列的[2,3-a]四 氫異喹?噁唑烷衍生化合物50,不僅具有高產率(85-98%)也有不錯的單一非鏡像 選擇性(>25:1)。利用NMR 光譜圖和X-ray 單晶繞射儀檢測並確定產物的相對立體 結構。本實驗室開發得此方法不僅符合現今所提倡的綠色化學理念,也擁有原子 經濟性的優點。
1,3-Oxazolidine frameworks were found in natural products and pharmaceutical compounds. In this research, addition of -hydroxy-,-unsaturated ketones 30 with 3,4-dihydroisoquinolines 49 provided oxazolo[2,3-a]tetrahydroisoquinoline 50 derivatives via tandem reaction involving nucleophilic addition and aza-Michael addition. The reaction proceeded under mild condition without catalyst and finished in 15 minutes, giving the various products with good to excellent yields (85-98%) and high diastereoselectivity (up to 25:1 dr). The relative stereo-structure of the products were confirmed by NMR technique and X-ray crystallography. This synthetic strategy corresponded with “green chemistry” and atomic economy.