Dehydrochlorination of 4-hydroxy-3,5-di-tert-butylbenzylidene chloride with aprotic nonionogenic reagents

Abstract

47 We showed previously that 4-hydroxy-3,5-ditertbutylbenzylidene chloride ( I ) reacted with nonionogenic aprotic reagents, such as triethyl orthoformate ( II ) [1] and esters of phosphorus(III) acids ( III ) [2], via nucleophilic displacement and underwent dechloroalkoxylation and dechlorophosphorylation to form acetal and diphosphonate, respectively. We studied previously unknown reactions of gemdichloride I with ethylene oxide ( IV ), vinyl ethyl ether ( V ), N , N , N ', N 'tetramethylmethanediamine ( VI ), and dimethyl(4hydroxy-3,5-ditertbutylbenzyl)amine ( VII ). The aim of this study is to establish the structure of reaction products and to determine the general reaction scheme and reaction conditions. We have found that, as distinct from reagents II and III , compounds IV – VII show dehydrochlorinating ability toward gemdichloride I . The main reaction product is 4-chloromethylene-2,6-ditertbutylcyclohexadien-2,5-one VIII . The coproducts of the reaction are ethylene chlorohydrin ( IX ), 1-chloro-1-ethoxyethane ( X ), dimethylamine hydrochloride ( XI ), dimethyl(chloromethyl)amine ( XII ), and amine hydrochloride XIII , respectively.