JPS6067457A - Production of bis(2-aminoethyl)sulfide - Google Patents

Abstract

PURPOSE:To reduce the amount of sodium sulfide to be used, suppress the formation of hydrogen sulfide and obtain the titled compound useful as an intermediate for agricultural chemicals and medicines, etc. without side reactions, by reacting a halogenated ethylamine hydrohalide with sodium sulfide in the presence of a caustic alkali. CONSTITUTION:A halogenated ethylamine hydrohalide, e.g. chloroethylamine acetate, is reacted with sodium sulfide in the presence of a caustic alkali, e.g. NaOH or KOH, to give bis(2-aminoethyl)sulfide. Sodium sulfide.nonahydrate as the above-mentioned sodium sulfide is used in an amount of almost equivalent amount, preferably 1.0-1.1 equivalents based on the halogenated ethylamine hydrohalide. Water is used as a reaction solvent, and the temperature is within 20-100 deg.C range.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing bis(2-aminoethyl) sulfide.

Bis(2-aminoethyl) sulfide is an agricultural chemical intermediate,
It is a particularly useful compound as a photographic agent, a raw material for polymeric compounds, etc.

The following method is known as a method for producing this bis(2-aminoethyl) sulfide.

That is, (1) a method of synthesizing ethyleneimine by reacting hydrogen sulfide or sodium sulfide (Ger.

0ffen, 722,944).

(2) A method based on the reaction of aminoethyl sulfate and sodium sulfide (Fr, 1.238, 350).

(3) Method by reaction of chloroethylamine with sodium sulfide (Ger, Offen, 2,441.741).

However, in method (1), the ethyleneimine used is carcinogenic and is not an industrially desirable method. Also,
In method (2), the reactivity of amine ethyl sulfate is low and the reaction takes a long time. Furthermore, since method (3) involves the reaction of chloroethylamine hydrochloride and sodium sulfide, it has the disadvantage that an excess of sodium sulfide is required and toxic hydrogen sulfide is generated.

The present inventors have intensively studied a method for producing bis(2-aminoethyl) sulfide that eliminates the above-mentioned drawbacks of the conventional method. As a result, the method of the present invention was discovered and completed.

That is, the present invention is a method for producing bis(2-aminoethyl) sulfide, which is characterized by reacting a halogenated ethylamine hydrogen halide salt with sodium sulfide in the presence of a caustic alkali.

According to the method of the present invention, the amount of sodium sulfide used can be reduced compared to the conventional method, so generation of toxic hydrogen sulfide can be suppressed. Moreover, since the reaction is with sodium sulfide in the presence of caustic alkali, free halogenated ethylamine, which is unstable under alkaline conditions, immediately reacts with sodium sulfide, thereby suppressing side reactions.

Chlorethylamine hydrochloride and bromoethylamine hydrobromide are often used as the halogenated ethylamine hydrogen halide salt used in the method of the present invention.

In addition, as caustic alkali, alkali metal hydroxide,
Caustic soda and caustic potash are usually used.

Theoretically, it is necessary to use an equivalent amount of caustic alkali to the halogenated ethylamine hydrogen halide salt, and at least
More than an equivalent amount is used, preferably 1.0 to 1.1 equivalents.

Further, for the sodium sulfide used in the present invention, the sodium sulfide nonahydrate is used in an amount of y equivalent, preferably 1.0 to 1.1 equivalent, relative to the halogenated ethylamine hydrogen halide salt. In the method of the present invention, water is used as a reaction solvent in consideration of the solubility of the halogenated ethylamine hydrogen halide salt and sodium sulfide.

The reaction is carried out in such a manner that the halogenated ethylamine hydrogen halide salt is in a free form with caustic alkali and is then reacted with sodium sulfide. Particularly preferred is a method in which an aqueous solution of a halogenated ethylamine hydrogen halide solution is dropped into a mixed aqueous solution of caustic alkali and sodium sulfide nonahydrate, and after the dropwise addition is completed, the reaction is heated until the reaction is completed.

In this embodiment, the concentration of the aqueous solution of sodium sulfide nonahydrate and caustic alkali is not particularly limited, but is preferably 1 to 5 mol/l. Further, the concentration of the aqueous solution of the ethylamine hydrogen halide salt is not particularly limited, but is preferably 0.1 to 5 mo I/l.
It is.

The reaction temperature is in the range of 20 to 100°C, and the reaction is usually completed in 30 minutes to 50 hours, although it varies depending on various reaction conditions.

After the reaction is completed, water is distilled off, and alcohol is added to the residue to precipitate by-produced common salt, which is then separated.

As the alcohol, methanol, ethanol, isopropyl alcohol, etc. can be used.

After removing the salt, the alcohol is distilled off, followed by vacuum distillation to obtain the desired bis(2-aminoethyl) sulfide.

The present invention will be explained below with reference to Examples.

Example 1 In a 11 four-bottle flask equipped with a stirrer, a thermometer, and a condenser, 120 ml (0.5 mol') of sodium sulfide/nase hydrate and 40 ml of caustic soda were added. 7 (1,0 mol) and water, 25
After charging 0 rnl, a solution of 240 ml (1 mol) of chloroethylamine hydrochloride dissolved in 250 ml of water was added dropwise at room temperature over 30 minutes. After the dropwise addition, the reaction was carried out at 80°C for 6 hours and then concentrated to dryness. Add ethanol to the residue and separate the precipitated salt.

The P solution was concentrated under reduced pressure to remove ethanol, and vacuum distillation was performed to obtain bis(2-aminoethyl) sulfide 52q (yield: 9
5%). Boiling point 102-104℃/5 niHg
.

Example 2 Sodium sulfide nonahydrate, 120
'l (0.5 mol) and 56 ml of caustic potassium (], ,
After adding 250 pieces of Ono I) and water, ethylamine bromide hydrobromide 2059 (1, Omol
) to 2507n! A solution of , dissolved in water is added dropwise at room temperature for 30 minutes. After the dropwise addition, the reaction was carried out at 50°C for 5 hours and then concentrated to dryness. Add ethanol to the residue and separate the precipitated potassium bromide.

The f solution was concentrated under reduced pressure to remove ethanol, and vacuum distillation was performed to obtain 44 bis(2-aminoethyl) sulfides (yield: 8
0) was obtained.

Patent applicant Mitsui Toatsu Chemical Co., Ltd.

Claims (1)

[Claims] 1) A method for producing bis(2-aminoethyl) sulfide, which comprises reacting a halogenated ethylamine hydrogen halide salt with sodium sulfide in the presence of a caustic alkali.