Synthesis of Bioactive Heterocycles: Aza-Claisen Rearrangement of 4-<b><i>N</i></b>-(4"-Aryloxybut-2"-ynyl),N- methylamino[1]benzothiopyran-2-ones
作者:K. Majumdar、S. Samanta
DOI:10.1055/s-2002-19309
日期:——
The hitherto unreported 4-(aryloxymethylene-1-methyl-1,2,3-trihydropyrido[3,2-c]benzothiopyran-5-ones are synthesized in 60-90% yield by the thermal aza-Claisen rearrangement of 4-N-(4"-aryloxybut-2"-ynyl),N-methylamino[1]benzothiopyran-2-ones in refluxing 1,2-dichlorobenzene. 4-N-(4"-Aryloxybut-2"-ynyl),N-methylamino[1]benzothiopyran-2-ones were prepared in 80-90% yields by the reaction of 4-chloro[1]benzothiopyan-2-one and appropriate 1-aryloxy-N-methylaminobut-2-ynes in refluxing ethanol. 4-Chloro[1]benzothiopyran-2-ones was in turn synthesised from 4-hydroxythiocoumarin by reaction with phosphorous oxychloride at 140 °C.
通过 4-N-(4"-芳氧基丁-2"-炔基),N-甲基氨基[1]苯并噻喃-2-酮在回流的 1,2-二氯苯中的热氮-克莱森重排反应,合成了迄今未报道的 4-(芳氧基亚甲基-1-甲基-1,2,3-三氢吡啶并[3,2-c]苯并噻喃-5-酮,收率为 60-90%。通过 4-氯[1]苯并噻喃-2-酮和适当的 1-芳氧基-N-甲基氨基丁-2-炔在回流乙醇中的反应,制备了 4-N-(4"-芳氧基丁-2"-炔基),N-甲基氨基[1]苯并噻喃-2-酮,收率为 80-90%。而 4-氯[1]苯并噻喃-2-酮又是由 4-羟基硫代香豆素在 140 °C 下与氧氯化磷反应合成的。