Electrochemical reduction of .alpha.,.alpha.'-dibromo-p-xylene

Syntheses of quaternary ammonium-containing, trithiocarbonate RAFT agents and hemi-telechelic cationomers

“…These compounds have been prepared by the monoquaternization of a,a 0 -dibromo-p-xylene by driving the precipitation of the mono-substituted compound out of the reaction solution. [35][36][37] Two previous examples in the polymer literature of the synthesis of these types of compounds are 4-(bromomethyl)-N,N,N-trimethyl benzyl ammonium bromide used to prepare a dithiocarbamate initer 13 and 4-(bromomethyl)-N-dodecyl-N,Ndimethylbenzyl ammonium bromide, 24 which was used as an initiator in the cationic polymerization of poly(methyloxazoline)s. However, these compounds have not previously been investigated for the synthesis of trithiocarbonate RAFT agents. In this article, in addition to presenting the reaction conditions for the synthesis of 4-(bromomethyl)-N,N,N-trialkylbenzyl ammonium compounds and subsequent RAFT agents, the purication of the polymers produced with these RAFT agents to produce high purity hemitelechelic cationomers is discussed.…”

Poly(P‐xylylene)s: Synthesis, polymer analogous reactions, and perspectives on structure–property relationships

“…Films of PPXs were obtained by electrolysis of 1,4bis(bromomethy1)benzene [72,73], which was also used for coating of carbon fibers with PPX [74]. The formation ofpquinodimethanes as intermediates was demonstrated by electrolysis of 1,4-bis(trichlorornethyl)benzene at -1 0 "C and isolation of a,a,a',a'-tetrachloro-p-xylylene, which polymerized at room temperature to poly(u.,a,u',u'-tetrachloro-p-xylylene) or formed 1,4-bis(bromodichloro-methy1)benzene by reaction with bromine (Scheme 8) [72].…”

Application ofo-Quinodimethanes in Organic Synthesis

“…邻苯碳醌的光化学反应在立体化学中也有应用, 此外, 还有一些较不常见合成邻苯碳醌的光化学方 法, 如 Furukawa 等 [41,42] [43] . 截至目前, 电化学产 生各种类型邻苯碳醌已是非常简便的方法 [1] , 尤其是电 化学产生邻苯碳醌的方法能够避免产生有害无机残留 物, 因此, 近年来引起了较广泛关注, 邻苯碳醌的氧化 还原反应也相继得到综述 [44] .…”