- 作者: 周善行 ; 劉勢勇 ; 蔡琮瑩
- 作者服務機構: Dept. of Chemistry, Fujen Univ., R.O.C.
- 中文摘要: Substituted 3-(phenylthio)-3-sulfolenes (3) and (4) are good precursors for 2-(phenylthio)-1,3-butadienes (5) and (6). The Diels-Alder reaction of the dienes derived from (3) and(4) with various dienophiles was studied. It was found that heating of sulfolenes (3) with methyl propiolate and N- phenylmaleimide afforded the Diels-Alder adducts of (5) directly and with complete regio- and stereospecificity. The same reaction with methyl vinyl ketone gave a mixture of endo and exo addition products. If sulfolenes (3) were first converted to the dienes (5) using lithium aluminum hydride and then reacted with methyl vinyl ketone in the presence of anhydrous zinc chloride, the stereoselectivity could be improved. Sulfolenes (4) also underwent cycloreversion/ cycloaddition with methyl acrylate, methyl vinyl ketone, and N-phenylmaleimide, but gave mostly the double bond-isomerized cycloaddition products. The regiochemistry of cycloaddition was delicately dependent on the dienophiles used.
- 英文摘要: --
- 中文關鍵字: 3-Sulfolenes; Sulfur-Substituted Dienes; Diels-Alder Reaction
- 英文關鍵字: 環戊二烯;硫取代二烯;狄爾斯-阿德爾反應