Piperazine was found to react with 1,2-dichloroethane to give first 1-(2-chloroethyl)piperazine, and then 3-azonio-6-azospiro [2,5]octane chloride as confirmed by experimental data and 1 H, 13 C, 15 N spectroscopy [1]. The 3-azonio-6-azospiro[2,5]octane chloride reacts with piperazine to form dipiperazinylethane. This suggests that it would not be possible to direct the reaction toward the production of the monosubstituted product while suppressing the formation of the disubstituted product. This is also observed in the case of the reaction of 1,2-dichloroethylene with morpholine in aqueous alkaline medium in the presence of triethylbenzylammonium chloride (TEBACH) to give 1,2-bismorpholinoethylene in 65.5% yield [2].Aiming at the synthesis of 1-(2-chloroethyl)morpholine II, in the present work we carried out the alkylation of morpholine I with dichloroethane in a liquid-liquid system in the presence of triethylbenzylammonium chloride as a phase-transfer catalyst.Our studies on the alkylation of morpholine I with 1,2-dichloroethane showed that the course of this simple reaction depends on the sequence of the reagents addition. Thus, when the reagents were added simultaneously, the alkylation of morpholine I with 1,2-dichloroethane (molar ratio 1:10) results in 1,2-bismorpholinoethane III in 70% yield. In this case 1-(2-chloroethyl)morpholine II was not detected in the reaction mixture. When morpholine was added dropwise within several hours at the same reagents ratio the reaction products were 1-(2-chloroethyl)morpholine II and 1,2-bismorpholinoethane III (2:1).Based on these data, we can assume that the reaction of 1-(2-chloroethyl)morpholine II with morpholine I occurs as a direct nucleophilic substitution of the chlorine atom by the S N 1 mechanism [3], but not through the formation of an intermediate compound
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.