Synthesis and electronic effect of the substituents on anionic ring-opening polymerization of para-substituted phenyl cyclopropanes
作者:Jin-Bong Kim、Iwhan Cho
DOI:10.1016/s0040-4020(97)00954-x
日期:1997.11
resulting polymers. The rate constants of polymerization(kp) in DMSO by 2 mole% cyanide ion at 35°C were p-MeO=0.45, p-Me=0.14, p-H=0.07, p-Cl=0.06 and p-NO2=0.011 liter/mole.sec, and the rate constants of polymerization in DMSO by 5 mole% pyridine at 35°C were p-Me0=0.048, p-Cl=7.6 × 10−3 and , respectively. The electronic effect exerted by substituents were well consistent with the Hammett relationship(log
作为具有电子推挽式取代基的活化环丙烷的阴离子聚合的研究的延伸,制备了具有MeO,Me,H,Cl和NO 2作为取代基的对位取代的苯基环丙烷-1,1-二腈。通过确定聚合反应的速率常数,转化率和所得聚合物的分子量,检查了取代基对阴离子聚合反应中开环反应的电子影响。在35°C下,2摩尔%氰化物离子在DMSO中的聚合速率常数(k p)为p-MeO = 0.45,p-Me = 0.14,pH = 0.07,p-Cl = 0.06和p-NO 2 = 0.011升/摩尔·秒,在35°C下5摩尔%吡啶在DMSO中聚合的速率常数为p-Me0 = 0.048,p-Cl = 7.6×10 -3和。被取代基所施加的电子效果均与哈米特关系以及一致的(对数K /ķ ö = σ ρ)时布朗的σ +中使用的常数。由氰化物离子引发剂获得的反应灵敏度常数(ϱ)对于吡啶引发为-1.0和-0.94。这些结果表明,对-取代的苯基环丙