Ring-selective synthesis of O-heterocycles from acyclic 3-O-allyl-monosaccharides via intramolecular nitrone–alkene cycloaddition
作者:Tony K.M Shing、Yong-Li Zhong
DOI:10.1016/s0040-4020(00)01138-8
日期:2001.2
Intramolecular 1,3-dipolar cycloadditions of nitrones formed from 3-O-allyl-d-glucose and d-altrose (both with threo-configuration at C-2,3) afford oxepanes selectively whereas the same reactions of nitrones derived from 3-O-allyl-d-allose and d-mannose (both with erythro-configuration at C-2,3) give tetrahydropyrans selectively.
由3 - O-烯丙基-d-葡萄糖和d-altrose(均在C-2,3处具有苏-构型)形成的硝酮的分子内1,3-偶极环加成反应可选择性地提供氧杂环丁烷,而衍生自3-的硝酮的相同反应O-烯丙基-d-阿洛糖和d-甘露糖(在C-2,3处均具有赤型构型)选择性地产生四氢吡喃。