DE1129961B - Process for the production of ring-shaped thiophosphoric acid esters - Google Patents

Description

Process for the preparation of cyclic thiophosphoric acid esters The invention relates to a process for the preparation of cyclic thiophosphoric acid esters of the general formulas in which R, R1, R2, R3, R4 and R5 are hydrogen atoms or alkyl radicals, R3 and R7 are hydrogen atoms, alkyl, aryl, aralkyl or alkaryl radicals, R8 is an alkyl, aryl, alkaryl or aralkyl radical and n is the number 1 or 2, in the event that 71 = 2, the radicals R6 and R7 on one side of the keto group can only represent hydrogen atoms or alkyl radicals, which is characterized in that cyclic dithiophosphoric acids of the general formulas at temperatures between -20 and 1500C with single o; "ß-unsaturated ketones of the general formula in which R6, R7 and R8 have the meaning given above, or with doubly x, -unsaturated ketones of the general formula in which R3 and R7 on one side of the keto group only represent hydrogen atoms or alkyl radicals and on the other side of the keto group have the meaning given above.

The reaction is carried out at temperatures from -20 to 150 ° C. However, temperatures of from 25 to 100 ° C. are preferably used in order to avoid yield losses to be avoided by decomposition with elimination of hydrogen sulfide. Will be common one the reactant dropwise to a solution or Suspension of the other reactant in an inert solvent or diluent admittedly, however, mixtures of either the simple or. of the doubly α, ß-unsaturated ketones with the; cyclic dithiophosphoric acids be reacted, the molar ratio in the case of using a simply oc, ß-unsaturated ketone can be from 0.25: 1 to 3: 1, while at Use of a doubly o;, ß-unsaturated ketone at least 2 moles of the ring-shaped Dithiophosphoric acid per mole of ketone are required.

If appropriate, the reaction can also be carried out in the presence of an aliphatic tertiary amine as a catalyst, such as triethylamine, or an anhydrous alkali metal hydroxide or carbonate.

If the unsaturated ketone is very reactive, the reaction will preferably carried out in the presence of a polymerization inhibitor such as hydroquinone.

The reaction is usually carried out in the presence of an inert organic Solvent carried out, especially when one or both reactants are solid substances. Usable solvents are e.g. B. saturated esters of fatty acids, such as ethyl acetate, amyl acetate, methyl propionate and methyl or. Ethyl butyrate; Ketones, such as acetone and methyl isobutyl ketone; Ethers such as dioxane; aromatic compounds, such as benzene, toluene, xylenes and nitrobenzene; chlorinated solvents such as carbon tetrachloride, Chloroform and chlorobenzene.

The ring-shaped thiophosphoric acid esters prepared according to the invention are obtained from the reaction mixture by fractional distillation.

However, the reaction mixture is preferably first diluted with a aqueous sodium bicarbonate solution or an equivalent agent and then with water washed, and the washed product is unreacted and the Freed solvent by high vacuum distillation. The cyclic thiophosphoric acid ester is then obtained in good purity as a distillation residue.

If necessary, the purification can be repeated if the process product should be obtained in even greater purity.

As unsaturated ketones in the process according to the invention for example: methyl vinyl ketone, ethyl vinyl ketone, butyl vinyl ketone, Decyl vinyl ketone, octadecyl vinyl ketone, phenyl vinyl ketone, benzyl vinyl ketone, tolyl vinyl ketone, Benzalacetone, benzalacetophenone, methyl-2,2-dimethylvinylketone (mesityloxide), divinylketone, Bis (2-methylvinyl) ketone, bis (2,2-dimethylvinyl) ketone (Phoron), phenyl-2-benzyl vinyl ketone, Phenyl 2-tolyl vinyl ketone, methyl 2-methyl vinyl ketone, ethyl 2-methyl vinyl ketone, isobutenyl propyl ketone, Isobutylidene acetone.

The following equation illustrates the course of the reaction when, for example, as ring-shaped phosphorodithioic acids. B. 2-mercapto-2-thiono- 1, 3,2-dioxaphospholane and as a, xB-unsaturated ketones z. B. simply o; "B-unsaturated ketones can be used.

The ring-shaped phosphorodithioic acids to be used as starting material can be made according to patent 1,024,090.

The ring-shaped thiophosphoric acid esters prepared according to the invention Can be used as insecticides, fungicides, plasticizers, rust inhibitors, foam flotation agents and additives for petroleum can be used.

The following examples illustrate the method according to the invention.

Example 1 To a solution of 34 g (0.23 mol) kept at 25 "C Benzalacetone in 75 g of benzene were added dropwise with stirring over 5 minutes 60 g (0.25 mol) of 5-ethyl-4-propyl-2-lnercapto -2-thionol, 3,2-dioxaphosphorinane were added. The reaction mixture was left to stand at 250 ° C. for 20 hours, then it was with neutralized with an excess of concentrated aqueous sodium bicarbonate solution and then washed with water until neutral to litmus. then the mixture was dried over calcium sulfate, filtered and the filtrate under a pressure of less than 2 mm up to a bubble temperature of 50 "C distilled.

79 g of 2- (2'-acetyl-l'-phenylethylmercapto) -5-ethyl-4-propyl-2-thiono-1,3,2-dioxaphosphorinane were obtained obtained in the form of an orange-colored, viscous liquid residue with the following properties: 30 = 1.5600; Acidity 0.04 cc of sodium hydroxide solution per gram.

Analysis in percent by weight: Found ... P 7.94, S 16.36, C 56.49, H 7.15; calculated . . P 8.02, S I 6.59, C 55.98, H 7.05.

Yield 88% of theory, based on benzalacetone.

EXAMPLE 2 A solution of 75 (0.33 mol) 5,5-diethyl-2-mercapto-2-thiono-1,3,2-dioxaphosphorinane in 150 g of toluene was added with stirring over the course of 10 minutes to a solution kept at 37 ° C. A solution of 21 g (0.152 mol) of Phoron in 25 g of toluene was added. After the reaction mixture had stood at 25 ° C. for about 20 hours, it was neutralized, as described in Example 1, with a sodium bicarbonate solution, washed, dried and filtered. The filtrate obtained was distilled under a pressure of less than 2 mm up to a bubble temperature of 100 ° C. 71 g of a reaction product of the formula were obtained obtained as a viscous residue with the following properties: n300 = 1.5532, acidity 0.01 ccm n-potassium hydroxide solution per gram, content of the sodium salt of the cyclic thiophosphoric acid 0.005 ccm n-superchloric acid solution per gram.

Analysis in percent by weight: Found ... P 10.39, S20.60, C 47.44, H 7.67; calculated ... P 10.48, S 21.70, C 46.78, H 7.50.

Yield 79% of theory, based on Phoron.

Example 3 48 g (0.2 mol) of 5-ethyl-4-propyl-2-mercapto-2-thiono-1,3,2-dioxaphosphorinane were stirred within 5 minutes to a solution of 37.5 g (0, 18 mol) of benzalacetophenone were added to 75 g of benzene, the temperature of the reaction mixture being kept at 25 ° C. The mixture was then stirred for 4 hours at 25 ° C., left to stand at this temperature overnight, then neutralized with concentrated aqueous sodium bicarbonate solution, twice with Washed water, dried over calcium sulfate and filtered. The filtrate obtained was distilled under a pressure of less than 2 mm to a bubble temperature of 50 "C. This gave 71 g of a waxy, solid residue which was stirred with 400 cc of ethyl ether and then filtered at 25" C. There were 12 g of 5 - ethyl - 4 - propyl - 2 - (2 '- benzoyl -1' - phenylethylmercapto) -2-thiono- 1,3,2-dioxaphosphorinane obtained as a white, solid residue with the following properties: F. 133 to 135 "C.

Analysis in percent by weight: Found ... P7.11, S14.30, C61.58, H6.47; calculated ... P 6.91, S 14.30, C 61.62, H 6.52.

Yield 15% of theory.

Example 4 To a solution of 9 g (0.062 mol) maintained at 25 "C Benzalacetone in 75 g of benzene were taking Stir within 10 minutes 15 g (0.071 Mol) 4,4,5,5-tetramethyl-2-mercapto-2-thiono-1,3,2-dioxaphospholane. After this the reaction mixture was allowed to stand at 25 "C for 50 hours, the mixture became neutralized with concentrated aqueous sodium bicarbonate solution, then with water washed, dried over calcium sulfate and filtered. The obtained filtrate became distilled under a pressure of less than 20 mm to a bubble temperature of 35 "C. The distillation residue was stirred with 300 ccm of ethyl ether, cooled to -25 "C, the mixture was filtered cold and the product, which was insoluble in ether, was air-dried.

14 g of 2- (2'-acetyl-1'-phenylethylmercapto) -4,4,5,5-tetramethyl-2-thiono-1,3,2-dioxaphospholane were obtained obtained as a fluffy gray solid residue with the following properties: F. 105 to 106 "C, acidity 0.004 ccm n-potassium hydroxide solution per gram, content of the sodium salt of the cyclic thiophosphoric acid 0.001 ccm n-superchloric acid solution per gram.

Analysis in percent by weight: Found ... P 8.87, S18.00, C 53.71, H 6.33; calcd ... P 8.64, S 17.89, C 53.61, H 6.46.

Yield 640 / o of theory, based on the benzalacetone.

EXAMPLE 5 98 g were added dropwise to 72 g (0.3 mol) of 5-ethyl-4-propyl-2-mercapto-2-thiono-1,3,2-dioxaphosphorinane at a temperature of 42 to 50 ° C. over the course of 20 minutes (1 mol) of mesityl oxide. The reaction mixture was stirred for a further 2 hours at 25 ° C. and then worked up and distilled according to the method described in Example 2. The distillation residue was dissolved in 300 cc of ethyl ether, the solution was washed first with aqueous, dilute sodium bicarbonate solution and then with water, dried over calcium sulfate and filtered. The filtrate obtained was distilled under a pressure of less than 4 mm to a bubble temperature of 50 ° C. 60 g of 2- (2'-acetyl-l ', l'-dimethylethylmercapto) -5-ethyl-4-propyl were obtained -2-thiono-1,3,2-dioxaphosphorinane obtained as a brown liquid residue with the following properties: molecular weight (ebullioscopic) 328.4 (theoretical 338.5); Acidity 0.001 ccm n-potassium hydroxide solution per gram, n00 = 1.5243.

Weight percent analysis: Found .... P8.86, S18.60, C 49.42, H 7.90; calcd ... P 9.15, S 18.94, C 49.67, H 8.05.

The yield was 590 / o of theory, based on the phosphorus Source material.

Example 6 To a solution of 64 g (0.3 mol) of 4,4,6-trimethyl-2-mercapto-2-thiono-1,3,2-dioxaphosphorinane in 100 g of toluene were added at a temperature of 25 to 30 " 98 g (1 mol) of mesityl oxide were added dropwise over the course of 20 minutes to C. The reaction mixture was stirred for a further 2 hours at 25 ° C. and then worked up and distilled according to the method described in Example 2. The distillation residue was dissolved in 300 cc of ethyl ether, the solution first washed with dilute, aqueous sodium bicarbonate solution and then with water, dried over calcium sulfate and filtered. The filtrate obtained was distilled under a pressure of less than 4 mm to a bubble temperature of 50.degree. 37 g of 2 - (2 '- acetyl -1 1' - dimethylethyl mercapto) - 2 - thiono-4,4,6-trimethyl-1,3,2-dioxaphosphorinane were obtained obtained as a brown, liquid residue with the following properties. n30 ° = 1.5304, acidity 0.03 ccm n-potassium hydroxide solution per gram.

Analysis in percent by weight: Found ... P 9.78, S19.90, C 45.59, H 7.13; calcd ... P9.98, S20.66, C 46.43, H 7.46.

The yield was 40% of theory.

Example 7 To a solution of 68 g (0.3 mol) of 5,5-diethyl-2-mercapto-2-thiono-1,3,2-dioxaphosphorinane in 200 g of toluene, while stirring at 42 to 50 ° C., 98 g (1st Mol) mesityl oxide added dropwise. The reaction mixture was then a further 2 Stirred for hours at 25 ° C., then with dilute, aqueous sodium bicarbonate solution neutralized, then washed with water and under a pressure of less than 2 mm distilled to a bubble temperature of 100 "C. The solid residue was dissolved in 500 cc of ethyl ether, the solution then with dilute aqueous sodium bicarbonate solution neutralized, washed with water, dried, filtered and the filtrate obtained cooled to -20 "C. The precipitate which separated out was filtered off, in 700 ccm of ethyl ether was dissolved and the solution was then cooled to -20 "C. The again precipitated Product was filtered off and stored at 25 "C and under a pressure of less than 4 mm dried.

There were 32 g of 2- (2'-acetyl-l ', l'-dimethylethylmercapto) -5,5-diethyl-2-thiono-1,3,2-dioxaphosphorinane obtained as a white solid body with the following properties: F. 65 to 70 "C, acidity 0.008 ccm of n-potassium hydroxide solution per gram.

Analysis in percent by weight: Found ... P 9.58, S19.10, C 47.88, H 7.70; calculated ... P 9.55, S 19.76, C 48.12, H 7.77.

Yield 330 / o of theory.

Claims (1)

PATENT CLAIM: Process for the preparation of ring-shaped thiophosphoric acid esters of the general formulas in which R, R1, R2, R3, R4 and R5 are hydrogen atoms or alkyl radicals, R6 and R7 are hydrogen atoms, alkyl, aryl, aralkyl or alkaryl radicals, R8 is an alkyl, aryl, alkaryl or aralkyl radical and n is the number 1 or 2, where, in the event that n = 2, the radicals R6 and R7 on one side of the keto group can only represent hydrogen atoms or alkyl radicals, characterized in that cyclic dithiophosphoric acids of the general formulas at temperatures between -20 and 150 ° C with single o; "ßunsaturated ketones of the general formula in which R6, R7 and R8 have the meaning given above, or with doubly α, ß-unsaturated ketones of the general formula in which R6 and R7 represent only hydrogen atoms or alkyl radicals on one side of the ketone group and have the meaning given above on the other side of the keto group