Title
Synthesis and chiroptical properties of helical polyallenes bearing chiral cholesteryl pendant groups
Author
Zhi-Peng Yu, Na Liu, Ya-Lan Lin, Jian Huang, Hui-Qing Wang, Zong-Quan Wu
Year
2017
Journal
Journal of Polymer Science Part A: Polymer Chemistry
Abstract
A cholesteryloxyallene (1) bearing chiral cholesteryl pendant group was designed and synthesized. Living polymerization of this monomer with an allylnickel complex as a catalyst give poly(cholesteryloxyallene)s (poly-1ms) in high yields with controllable molecular weights and narrow molecular weight distributions. These polymers were found to possess a dynamic helical conformation with a preferred handedness in n-hexane as confirmed by circular dichroism and absorption spectra as well as optical ratios. The helical conformation of the polymers was revealed to stabilize as the number of repeat units increased until the degree of polymerization reached 100. The helical conformation of poly-1100 could be controlled by altering the temperature of solutions.
Instrument
J-1500
Keywords
Circular dichroism, Polymers, Chemical stability, Thermal stability,