α-蒎烯合成樟脑醌的研究

Synthesis of camphorquinone from α-pinene

以α-蒎烯为原料,与HCl加成、异构得到2-氯莰烷,再经消除反应得到冰片烯,以丙酮-水混合溶剂为反应介质,高锰酸钾为氧化剂氧化冰片烯,得到樟脑醌。探讨了相转移催化剂及溶剂种类、KMnO4用量、丙酮与水的体积比,以及溶剂用量、反应温度、反应时间等对冰片烯氧化反应的影响,确定了适宜的氧化工艺条件:以高锰酸钾为氧化剂,高锰酸钾与冰片烯的物质量之比为3.0∶1;以丙酮-水混合溶剂作为氧化反应介质,丙酮与水的体积比为3∶1,丙酮-水混合溶剂与冰片烯的体积质量比为20∶1(mL/g);反应温度为30℃;反应时间4 h。在此工艺条件下,樟脑醌得率达85%以上。采用GC-MS、FTIR、1H NMR、13C NMR等分析手段对合成所得产物的化学结构进行了分析测定。

Synthesis of camphorquinone was carried out by using α-pinene as the starting material.2-chlorinated bornane was prepared by addition and isomerization of α-pinene and dry hydrogen chloride,and it was further eliminated HCl in order to obtain bornylene.Camphorquinone was finally obtained by oxidation of bornylene with KMnO4 in mixed acetone-water solvent.Influences of phase-transfer catalysts and solvent systems,the amount of KMnO4,acetone/H2O ratio and the amount of mixed solvent,reaction temperature and reaction time on the oxidation of bornylene were examined in detail,and the suitable oxidation conditions were determined as follows：KMnO4 was used as the oxidant for oxidizing bornylene into camphorquinone,and KMnO4/bornylene molar ratio was 3.0∶1;acetone/H2O mixture with a volume ratio 3∶1 was used as the solvent,and the solvent/bornylene ratio was 20∶1（mL/g）;the oxidation of bornylene was conducted at 30 ℃ for 4 h.The yield of camphorquinone was over 85% under the aforesaid conditions,and its chemical structure was determined with GC-MS,FTIR,1H NMR,and 13C NMR spectra.