DE1618146C3 - Process for the production of dithionoxalic acid diamides - Google Patents

Description

15th

The production of dithionoxalic acid diamide, which is unsubstituted on the nitrogen atoms, by Implementation of dicyan with hydrogen sulfide has been known for a long time (Annalen der Physik und Chemie, Vol. 24 [1832], pp. 167 to 172; Liebigs Annalen der Chemie, Vol. 38 [1941], p. 314; Reports of the German Chemical Society, Vol. 22 [1889],

P. 2655; Journal for practical chemistry, Vol. 29 [1884], P. 129). It is known that Ν, Ν'-disubstituted dithiooxamides according to the "Wallach reaction" made by simply mixing dithiooxamide with amines in an organic solvent (cf. J. org. Chemistry, 26, 1961, p. 3982 and p. 3985, left column, paragraphs 1 and 2). Dithionoxalic acid diamides can only be obtained with great difficulty in the way described. A in U.S. Patent 2531283 Process that converts vinyl ethers or esters with sulfur and amines to dithionoxalic acid diamides, unsatisfactory in terms of yield and uniformity of the end products.

It has now been found that dithionoxalic acid diamides are advantageously obtained when chloroethanes are used or chloroethene with sulfur and primary amines, with sulfur and amine respectively used in an approximately stoichiometric amount, based on the halogen compound, or in excess will.

The implementation can be represented by the following formulas:

CHCU-CHCl, + 2 S + 6

NH,

NH - C - C - NH

Il Il s s +4

NH ₃ CI

H ₂ C = CCl ₇ + 3S + 4

NH,

NH - C - C - NH

Il Il s s +2

NH ₃ Cl + H ₂ S

Cl ₃ C-CCl ₃ + 4S +

NH,

NH - C - C - NH

S S +2

NH ₃ Cl + 2SCl ₂

CH, - CH, C1 + 5S + 3

NH,

NH-C-C-NH

NH ₃ Cl + 3H ₂ S

S S

In comparison to the aforementioned method, the method according to the invention, starting from FIG easily accessible starting materials, a large number of dithionoxalic acid amides in a simple way good yield and purity.

Further z. B, also cis and trans-s-dichloroethylene can be used as a starting material.

About 2 gram atoms of sulfur per halogen compound are required to form the dithione group. However, the sulfur can also be used in excess. Amounts of about 3 to 5 gram atoms Depending on the constitution of the halogen compound, sulfur is useful to prevent hydrogen being released to bind or split off halogen; the optimal amount of sulfur in each case depends on the amount of the hydrogen or halogen to be bound, as the above formulas illustrate.

Primary amines are also used in the reaction. Used per mole of halogen compound about 2 moles of these basic starting materials to form the two dithionoxalic acid amide groups. However, the amines can also be used in excess. Quantities of about 3 to 6 mol these basic starting materials are expedient

depending on the constitution of the halogen compound to be used, to the liberated hydrohalic acid to tie. Instead of the amines, which serve to bind the acid, equivalents can also be used Amounts of other acid-binding agents are added to the reaction. As such are suitable z. B. tertiary amines, inorganic bases such as alkali or alkaline earth oxides, hydroxides, amides, alcoholates or salts of polybasic acids.

Preferred basic starting materials are those in their general formula

R,

R ₂

NH

R ₁ and R _{2 can be} identical or different and each represent an alkyl, cycloalkyl, aralkyl or aryl radical, in particular each having up to 20 carbon atoms.

So z. B. the following bases are used as basic starting materials: diethyl, ethyl, dibutyl, Dodecyl, ethylmethyl, cyclohexyl, cyclooctyl, benzyl, hexylmethylamine, aniline, naphthylamine.

The reaction is generally carried out at a temperature between 80 and 200 ^° C., preferably between 80 and 150 ^° C., without pressure or under pressure, continuously or batchwise. If necessary, organic solvents which are inert under the reaction conditions, such as aromatic hydrocarbons, e.g. B. benzene, toluene, xylene; Alcohols e.g. B. methyl, butyl alcohol, cyclohexanol; ether, e.g. B. dibutyl ether, dioxane.

The reaction can be carried out as follows: A mixture of the starting materials, optionally together with solvents and / or acid-binding agents, will be mixed well for some time held at the aforementioned temperature. The mixture is then cooled and filtered. The filter residue is washed free of chlorine ions with water and removed from a suitable solvent, e.g. B. n-butanol, recrystallized. The filtrate can be obtained by concentration of the solution, filtration and appropriate work-up of the deposited solid, further shares of the end product are obtained. You can do it Concentrate the filtrate completely and from the residue in the usual way, for. B. by distillation, the Isolate the end product.

The compounds which can be prepared by the process of the invention are valuable starting materials for dyes and herbicides.

The parts given in the following examples are parts by weight.

example 1

495 parts of cyclohexylamine and 64 parts of sulfur are heated ^{to 70 ° C. in 800 parts of toluene.} 131 parts of 1,1,1-trichlorethylene are gradually added to the mixture at this temperature. The mixture is then stirred for 10 hours at reflux temperature (110 ⁰ C). After the mixture has cooled to 5 ° C., the precipitate which has separated out is filtered off with suction and the filtrate is concentrated. The filter residue is washed free of chlorine ions with water and recrystallized together with the residue from the toluene filtrate using n-butanol. 182 parts of Ν, Ν'-dicyclohexyldithiooxalamide with a melting point of 152 ° C. (corresponds to 64% of theory, based on the trichlorethylene used) are obtained.

Example 2

396 parts of cyclohexylamine and 64 parts of sulfur in 500 parts of toluene are heated to 8O ⁰ C. 100 parts of 1,2-dichloroethane are gradually added to the mixture over the course of one hour. The reaction mixture is refluxed at about 115 ° C. for an additional 24 hours. Work-up analogous to that described in Example 1 gives 112 parts of N, N'-dicyclohexyldithiooxamide with a melting point of 152 ° C. (corresponds to 40% of theory, based on dichloroethane used).

Example 3

297 parts of cyclohexylamine, 128 parts of sulfur and 63 parts of vinyl chloride in 300 parts of benzene are ^{heated to 120 °} C. for 5 hours in a shaking autoclave. After cooling and releasing the pressure in the autoclave, the reaction mixture is freed from benzene, washed with water and recrystallized from ethyl alcohol. After separating off the excess sulfur, 187 parts of N, N'-dicyclohexyldithiooxamide with a melting point of 151 ° C. (corresponds to 66% of theory) are obtained.

Example 4

594 parts of cyclohexylamine, 96 parts of sulfur and 166 parts of symmetrical tetrachlorethylene are ^{heated in 800 parts of toluene to 100 to HO 0} C for 30 hours. After the mixture has cooled to about 5 ° C., the precipitated solid is filtered off with suction. The filter residue is washed free of chlorine ions with water and dried. The toluene solution is also washed with water, dried and concentrated to 1/3. The crystals formed in this way are filtered off with suction and recrystallized from n-butanol together with the 1st filter residue. This gives 179 parts of Ν, Ν'-Dicyclohexyldithiooxamid mp. 152 ⁰ C (corresponding to 64% of theory, based on tetrachlorethylene).

Example 5

450 parts / Ϊ-methoxyethylamine and 96 parts of sulfur are heated in 800 parts of ethyl alcohol at 60 to 70 ⁰ C and the mixture at this temperature 166 parts of sym. Tetrachlorethylene gradually added. The reaction mixture is stirred for 25 hours at reflux temperature and cooled to 5 to 10 ⁰ C. The precipitate formed is filtered off with suction, washed with water and recrystallized from ethyl alcohol. There are 121 parts of N, N'-di- / i-methoxy-äthyldithiooxamid mp. Obtained 9O ⁰ C. The combined alcohol filtrates are concentrated completely, and 500 parts of water are added. A further 36 parts of N, N'-di - /? - methoxylethyl-dithiooxamide are isolated from the water-insoluble residue. The total amount of end product corresponds to 67% of theory, based on the tetrachlorethylene used.

Example 6

535 parts of benzylamine and 64 parts of sulfur are heated to 70 ° C in 400 parts of ethyl alcohol 131 parts of 1,1,1-trichlorethylene for one hour

gradually admitted. The reaction mixture is heated to 85 ° C. for a further 20 hours and cooled down vigorously and filtered. The filter residue is washed free of chlorine ions with water, dried and removed n-butanol recrystallized. 124 parts of Ν, Ν'-dibenzyldithiooxamide with a melting point of 115 ° C. are obtained. The filtrate is concentrated completely, taken up in benzene, washed with water and dried. A further 37 parts of Ν, Ν'-dibenzyldithiooxamide can be obtained from the benzene solution by precipitation with ligroin be won. The total yield corresponds to 54% of theory, based on the trichlorethylene used.

B e i s ρ i e 1 7

295 parts of propylamine, 64 parts of sulfur and 400 parts of ethyl alcohol are heated to 70 ° C. and 131 parts of 1,1,1-trichlorethylene are gradually added. The reaction mixture is stirred for a further 20 hours at 80 to 85 ° C., cooled vigorously, and the precipitated hydrochloride is filtered off with suction. The filtrate is completely freed from ethanol, taken up in benzene, washed free of chlorine ions with water, dried and distilled. In Kp. _3130-135 ° C 127 parts of Ν, Ν'-dipropyl-dithiooxamide are obtained (corresponding to 62% of theory, based on trichlorethylene).

Examples

A mixture of 396 parts of cyclohexylamine, 128 parts of sulfur and 99 parts of 1,1-dichloroethane in 600 parts of ethyl alcohol is heated to 80 ° C for a total of 40 hours. After about 3 hours it sets strong evolution of hydrogen sulfide. After the evolution of hydrogen sulfide has ended (40 hours) is cooled to about 5 ° C. and the precipitated solid is filtered off with suction. The filter residue is in Suspended 300 parts of water, filtered and washed free of chlorine ions with water. After recrystallization 156 parts of N, N'-dicyclohexyldithiooxalamide are obtained from acetone. The ethanol filtrate is completely concentrated; and the residue is made from acetone with the addition of some activated charcoal recrystallized. 52 parts of Ν, Ν'-dicyclohexyldithiooxalamide are obtained. A total of 208 parts of Ν, Ν'-dicyclohexyldithiooxalamide with a melting point of 152 ° C. are obtained (corresponds to 73% of theory).

: ·. · ■. Example 1 9

A mixture of 119 parts of hexachloroethane and 396 parts of cyclohexylamine are added at 70 ° C. to a suspension of 32 parts of sulfur in 300 parts Ethanol was added in portions over the course of an hour. The reaction mixture is then still heated to 85 ° C for about 15 hours. After cooling down the precipitated solid is filtered off with suction, washed out with water and recrystallized from n-butanol. 52 parts of Ν, Ν'-dicyclohexyldithiooxamide are obtained (M.p .: 151-152 ° C); this corresponds to a yield of 36.5% of theory, based on hexachloroethane.

Claims (1)

Claim: Process for the production of dithionoxalic acid diamides, characterized in that one with chloroethanes or chloroethene Converts sulfur and primary amines, with sulfur and amine each being roughly stoichiometric Amount, based on the halogen compound, or used in excess.