Bis-2-aminoethyl sulfide

Forty-three grams (1.0 mole) of ethyleneimine (p. 153) (Caution— volatile and toxic substance) is placed in a flask equipped with a reflux condenser. The reaction mixture is held at 60° by external cooling while a stream of hydrogen sulfide is introduced. After there is no evolution of heat upon introduction of hydrogen sulfide (about 50 minutes), the liquid, viscous reaction mixture is dissolved in 1.25 times its volume of absolute ethanol and cooled overnight in the refrigerator. The precipitated /J-aminoethyl mercaptan (5.6 g.) is filtered off, and the ethanol is evaporated from the filtrate under reduced pressure. The residual liquid is distilled under reduced pressure, and 4.9 g. additional / -aminoethyl mercaptan sublimes during the first part of the distillation. Bis-2-aminoethyl sulfide is collected at 130-131 °/22 m. There is obtained 29.8 g., or a 50% yield. 

A solution of 122.2 g. (1.0 mole) of bis-2-hydroxyethyl sulfide ( Kromfax solvent, Carbide and Carbon Chemicals Corporation) and 978 g. of concentrated hydrochloric acid is heated under a reflux condenser to between 80° and 90° for 1 hour. (Use a good hood.) After the solution is cooled, the lower layer is separated and freed 

Extreme caution must be used in handling this material mustard gas ). Avoid all contact of the unprotected skin with the liquid or vapor since it is toxic and a potent vesicant (blistering agent). 

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Reaction with Sulfur Nucleophiles, Because sulfai is highly nucleophilic, reactions of aziridines with sulfur nucleophiles generally proceed rapidly (111) and with good yields. The reaction of hydrogen sulfide [7783-06S-J with ethyleneimine yields cysteamine [60-23-1] (2-mercaptoethylamine) or bis(2-aminoethyl)sulfide [871-76-1] (2,112) depending on the molar ratio of the reactants. The use of NaHS for the synthesis of cysteamine has also been described (113). 

The reaction of the anhydrides 60 with bis(2-aminoethyl) sulfide gave the sulfides 182, which were converted by the action of carbonic ester into compounds 183 [106, 107],... 

The reaction of carbon disulfide with 1,2-alkylene diamines (I) yields N-(2-aminoethyl) dithiocarbamic acids (II) which split off hydrogen sulfide thermally to give imidazolidine-2-thiones (III) (Hofmann-process). The simplest example, the reaction of carbon disulfide with ethylenediamine, is described in Organic Synthesis (5). The reaction is general for N,N -dialkyl-, N,N -diaryI, as well as for N,N -bis-(arylakyl) ethylene diamines. The rate of reaction is determined by the basicity of the diamine. Electron-donor substituents in the para-position of N-aromatically substituted ethylene diamines accelerate dithiocarbamate formation electron-acceptor groups retard it. 

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