| 1. | Hydroxyquinol triacetate was prepared from p - benzoquinone by 1 , 4 - addition reaction with acetic anhydride and then 6 , 7 - dihydroxy coumarin was synthesized from it by hydrolyze and cyclization in concentrated sulfuric acid . then 6 , 7 - dimethoxy coumarin was synthesized by methylating from 6 , 7 - dihydroxy coumarin with an overall yield of 74 . 4 % . the procedure was practical . its structure was confirmed by ir and 1hnmr
对苯醌与乙酸酐经1 , 4 -加成生成1 , 2 , 4 -苯三酚三乙酸酯,然后与苹果酸反应经水解、环合反应得6 , 7 -二羟基香豆素,再经甲基化得到6 , 7 -二甲氧基香豆素,总收率为74 . 4 % ,整个过程反应条件温和,操作方便,适合工业生产的要求,对产品结构进行了ir和1hnmr表征。 |
