Stable Helical Polyguanidines: Poly{<i>N</i>-(1-anthryl)-<i>N</i><i>‘</i>-[(<i>R</i>)- and/or (<i>S</i>)-3,7-dimethyloctyl]guanidines}
作者:Hong-Zhi Tang、Yujie Lu、Gonglu Tian、Michael D. Capracotta、Bruce M. Novak
DOI:10.1021/ja049937g
日期:2004.3.1
Using chiral catalysts of (R)- and/or (S)-BINOL-Ti, the asymmetrical polymerization of achiral monomer, N-(1-anthryl)-N'-n-octadecylcarbodiimide, yielded soluble nonregioregular polyguanidines of Poly-R1 and Poly-S1. A racemization process occurred when the toluene solution of Poly-R1 was annealed at elevated temperatures (70-80 degrees C). Kinetic studies reveal this to be a slow process with an activation
使用 (R)- 和/或 (S)-BINOL-Ti 的手性催化剂,非手性单体 N-(1-蒽基)-N'-n-十八烷基碳二亚胺的不对称聚合产生了 Poly-R1 和聚-S1。当 Poly-R1 的甲苯溶液在高温(70-80 摄氏度)下退火时,会发生外消旋化过程。动力学研究表明,这是一个缓慢的过程,活化能为约。36 大卡/摩尔。另一方面,使用钛(IV)三氟乙醇催化剂,N-(1-蒽基)-N'-[(R)-和/或(S)-3,7-二甲基辛基]碳二亚胺的聚合得到高度区域规整的聚胍聚-R2 和聚-S2。这些聚合物在各种溶剂和高温下采用稳定的螺旋,