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(1)用PPA作接触剂使癒瘡木酚和醋酸酐进行縮合,因醋酸酐用量不同得到兩种結果:第一,当癒瘡木酚和醋酐之量为当量时,产物为香莢蘭乙酮(Ⅰ);第二,当醋酸酐大过量时,产物为異香莢蘭乙酮(Ⅱ)的醋酸酯。反应演变过程的推論經实驗証明属实。 (2)用α-氯乙醯基作癒瘡木酚之羟基之封鎖基,然后再用PPA作接触剂,使之与醋酸酐、冰醋酸,丙酸或丁酸縮合,醯基即从甲氧基之对位进入得(Ⅳ),产率可达95％,因此癒瘡木酚轉变为(Ⅴ)的得量远較文献所报告者为佳。 (3)癒瘡木酚的α-氯醋酸酯在用PPA为接触剂的条件下,不易起Fries移位反应的事实,用电子理論加以解釋。
(1) PPA as a contact agent to make guaiacol and acetic anhydride condensation, due to the different amounts of acetic anhydride obtained two results: First, when the amount of guaiacol and acetic anhydride equivalent, the product is fragrant pods Acetophenone (Ⅰ); Second, when the acetic anhydride is excessive, the product is the acetates of isovantrone (Ⅱ). The corollary of reaction evolution is proved by experiment. (2) α-chloroacetyl group base for guaiacol hydroxy acid blockade, and then re-PPA as a contact agent, so that with acetic anhydride, glacial acetic acid, propionic acid or butyric acid condensation, the base from a Oxygen para into the (Ⅳ), the yield of up to 95%, so the conversion of guaiacol to (Ⅴ) yields much better than reported in the literature. (3) The fact that α-chloroacetate of guaiacol is not prone to Fries shift reaction under the condition of using PPA as contact agent is explained by electronic theory.