甲基环戊二烯的合成研究

Investigation of synthesis of methylcyclopentadiene

以环戊二烯(CPD)、金属钠和一氯甲烷为原料合成甲基环戊二烯,包括制备环戊二烯钠和环戊二烯钠甲基化两步反应。结果表明,反应温度及环戊二烯与钠的摩尔比对甲基环戊二烯的收率影响显著。双环戊二烯的最佳解聚温度为250℃,对于CPD与钠的反应,反应初期温度应控制在较低的温度,以减少CPD二聚反应;反应后期可将温度升高至28℃,以加快CPD与钠的反应速率。最佳的CPD与钠摩尔比为2.2,此时甲基环戊二烯的收率达86%。

Methylcyclopentadiene was synthesized from cyclopentadiene,metallic sodium and methane chloride by a two-step method,which included synthesis of cyclopentadiene sodium by reaction of cyclopentadiene with metallic sodium and successive methylation of cyclopentadiene sodium with methane chloride. The results showed that reaction temperature and ratio of cyclopentadiene to sodium in the first step can remarkably influence yield of methylcyclopentadiene. DCPD optimal solution polymerization temperature of 250 ℃,for the CPD and sodium reaction temperature should be controlled at a lower initial temperature to reduce the occurrence of the dimerization of CPD; later reaction temperature can be raised to 28 ℃,to accelerate the rate of reaction with Na and CPD. The optimal mole ratio of cyclopentadiene to sodium is 2. 2,then the yield of methylcyclopentadiene can reach 86%.