Synthesis of poly(1-hexene)s end-functionalized with phenols

Abstract

Electrophilic alkylations of phenol/2,6-dimethylphenol were performed with vinylidene-terminated poly(1-hexene)s using BF₃·OEt₂ catalyst. Vinylidene-terminated poly(1-hexene)s with M_n varying from 400 to 10000 were prepared by bulk polymerization of 1-hexene at 50 to -20 °C using Cp₂ZrCl₂/MAO catalysts. The phenol/2,6-dimethylphenol-terminated poly(1-hexene)s was characterized by NMR (¹H, ¹³C), UV, IR and vapor phase osmometer (VPO). The isomer distribution (ortho, para and ortho/para) was determined by ¹³P NMR using a phosphitylating reagent, namely 2-chloro-1,3,2-dioxaphospholane. The number-average degree of functionality (F_n) > 0.9 with > 95% para selectivity could be achieved using low-molecular-weight oligomers of poly(1-hexene)s.