Stereoselective formation of optically active 2-oxy-1,3-oxazolidin-4-ones from chiral O-acylmandelamides or lactamides

详细信息    查看全文

• 作者：Kamimura ; Akio ; Omata ; Yoji ; Kakehi ; Akikazu ; Shirai ; Masashi
• 关键词：orthoesters ; oxazolidinones ; stereoselection ; protecting groups
• 刊名：Tetrahedron
• 出版年：2002
• 出版时间：October 21, 2002
• 年：2002
• 卷：58
• 期：43
• 页码：8763-8770
• 全文大小：204 K

文摘

(−)-O-Acyllactamides or mandelamides in the presence of TBSOTf underwent cyclization reaction to give optically active 2-oxy-1,3-oxazolidin-4-ones, a novel nitrogen analog of orthoesters, in good yields. An X-ray analysis and NOE studies indicated that the absolute configuration at the newly formed chiral carbon was S. For their synthetic application, the 1,3-dipolar cycloaddition of nitrile oxide was examined. The cycloadducts were obtained in a stereoselective manner. Subsequent treatment of the adduct with TBAF resulted in the one-step removal of mandelamide, giving optically active 4,5-dihydroisoxazole and mandelamide in good yields.