Synthesis of Polyalkylphenyl Prop-2-ynoates and Their Flash Vacuum Pyrolysis to Polyalkylcyclohepta[b]furan-2(2H)-ones
作者:Matthias Nagel、Hans-Jürgen Hansen
DOI:10.1002/(sici)1522-2675(20000510)83:5<1022::aid-hlca1022>3.0.co;2-y
日期:2000.5.10
A new method for the smooth and highly efficient preparation of polyalkylated aryl propiolates has been developed. It is based on the formation of the corresponding aryl carbonochloridates (cf. Scheme 1 and Table 1) that react with sodium (or lithium) propiolate in THF at 25 – 65°, with intermediate generation of the mixed anhydrides of the arylcarbonic acids and prop-2-ynoic acid, which then decompose
开发了一种平稳高效制备多烷基化芳基丙酸酯的新方法。它基于形成相应的芳基碳酰氯(参见方案 1 和表 1),其与 THF 中 25-65° 的丙醇钠(或锂)反应,中间生成芳基碳酸和丙醇的混合酸酐-2-ynoic acid,然后几乎定量地分解成 CO2 和芳基丙酸酯(参见方案 11)。该过程优于将丙炔酸转化为其难以处理的酰氯,然后与芳醇钠(或锂)反应。许多多烷基化芳基丙炔酸酯在 600 – 650° 和 10-2 Torr 下进行闪蒸真空热解 (FVP),导致形成相应的环庚[b]furan-2(2H)-ones,平均产率为25 – 45%(参见方案 14)。在中试实验中进一步发现,多烷基化的 cyclohepta[b]furan-2(2H)-ones 与甲苯中的 1-(pyrrolidin-1-yl)cyclohexene 在 120 – 130° 下反应生成相应的 1,2, 3,4-四氢苯并[