A Wittig-olefination–Claisen-rearrangement approach to the 3-methylquinoline-4-carbaldehyde synthesis
作者:Mukund G Kulkarni、Mayur P Desai、Deekshaputra R Birhade、Yunus B Shaikh、Ajit N Dhatrak、Ramesh Gannimani
DOI:10.3762/bjoc.8.197
日期:——
rearrangement to give 4-pentenals 3a-h. Protection of the aldehyde group of the 4-pentenals as acetals 4a-h and subsequent oxidative cleavage of the terminal olefin furnished nitroaldehydes 5a-h. Reductive cyclization of these nitroaldehydes yielded the required 3-methylquinoline-4-carbaldehydes 6a-h in excellent yields. Therefore, an efficient method was developed for the preparation of 3-methylquinoline-4-carbaldehydes
描述了使用 Wittig-烯烃化-克莱森重排协议从邻硝基苯甲醛 1a-h 合成重要的 3-甲基喹啉-4-甲醛 6a-h 的有效合成。邻硝基苯甲醛与巴豆氧基亚甲基三苯基膦的 Wittig 反应得到巴豆基乙烯基醚 2a-h,在二甲苯中回流加热时,其经历克莱森重排得到 4-戊烯醛 3a-h。将 4-戊烯醛的醛基保护为缩醛 4a-h,随后氧化裂解末端烯烃提供硝基醛 5a-h。这些硝基醛的还原环化以极好的收率产生了所需的 3-甲基喹啉-4-甲醛 6a-h。所以,