CS215477B1 - Method of preparation of s-chlormethylesters of mixed dithiophosphoric acids - Google Patents

Description

The present invention provides a process for the preparation of mixed dithiophosphoric acid chloromethyl esters. Said compounds are effective as soil insecticides.

S-chloromethyl esters of dithiophosphoric acids of the formula I are known from the literature

P - S - CH? - Cl in which R and R 'are C 1 -C 4 alkyls, n is 0 or 1, effective as insecticides. They are prepared by reacting bromochloromethane with a potassium salt of dithiophosphoric acid, respectively. of dithiophosphonic acid in the medium of methyl ethyl ketone or acetone for 5-7 h, with bromochloromethane being used in 100% excess, yield of 60 to 80% (Austr. pat. 432.101).

Also known are the insecticidally active S-chloromethyl esters of the thio- and dithiophosphoric acids of the general formula II in which R and R 'are alkyl of 1 to 4 carbon atoms, X and Y are oxygen or sulfur and m is 0 or 1. These are prepared from the respective salts of organophosphoric acids with bromochloromethane in a ketone environment, the bromochloromethane being used in a 100% excess in a yield of 50 to 80% (US Pat. 3,896,219; DOS, 1,925.468).

S-chloromethyl Ο, dial-dialkyldithiophosphates, which can be prepared by reaction of bromochloromethane with potassium dithiophosphoric acid in an excess of bromochloromethane at 60 ° C for 24 h, are also known as topical insecticides, yielding a 60% yield. Similarly, the reaction can be carried out in methanol in the presence of potassium iodide as a catalyst in a yield of 71% (DOS 1.015.794).

He has now been found a new process for the preparation of S-chloromethyl mixed dithiophosphoric acid III-V / IC _{4 g} of H / _{2 PS-CH2} -C

P - Y - CH, R. ²

- Cl

X by reaction of bromochloromethane with a mixture of dithiophosphoric acids, or a mixture of their salts of formulas VI-VIII /: ₂ K ₅ e / ₂ P - SM / S ^s / ^m ₄ H ₉ o / ₂ P-SM s M means hydrogen, ammonium, alkali metal, in particular sodium or potassium, preferably using an excess of bromochloromethane.

The invention is based on the fact that the reaction is carried out in an aqueous medium in the presence of a quaternary ammonium salt catalyst of the formula IX

R ¹ is C 1 -C 18 alkyl R ² is C 1 -C 4 alkyl optionally substituted with bromine,

R ³ is C 1 -C 4 alkyl or propargyl

R ⁴ is C 1 -C 4 alkyl, cyclohexyl, benzyl, 1,6-hexylene,

R ¹ and R ² together with the nitrogen of the quaternary ammonium salt can form a 5-6 membered heterocyclic ring in which oxygen can be another heteroatom,

Y represents halogen -Cl, -Br, -I, in an amount of 1 to 10 mol%, the reaction proceeding at a temperature of 20 ° C to the reflux temperature of the reaction mixture. The preparation of the S-chloromethyl esters of mixed dithiophosphoric acids according to the invention has the advantage over the prior art in that substantially higher yields of approximately 30% are achieved and at the same time the reaction time is halved. Both of these factors significantly affect production technology.

The following examples illustrate but do not limit the scope of the invention.

Example 1

To 248.4 g of bromochloromethane (1.92 mol) at reflux temperature (68 ° C) and vigorous stirring was added 452.5 g of an aqueous solution of potassium dithiophosphoric acid (0.96 mol) over 1 hour. After addition, the contents were stirred at the same temperature for 1 h, after cooling the reaction mixture, the crude product was separated. From it, excess bromo-chloromethane was distilled off under reduced pressure.

The distillation residue 171 g contained:

13.6% of O, O-diethyl S-chloromethyldithiophosphate

44.5% O-ethyl-O-isobutyl-S-chloromethyldithiophosphate 31.9% O, O-diisobutyl-S-chloromethyldithiophosphate.

The analysis was determined by gas chromatography in relation to the standards used, given by weight. The total yield calculated on the starting potassium salt of mixed dithiophosphoric acids is 61%.

Example 2

To 328.8 g of 95% bromochloromethane (2.81 mol) at reflux temperature (68 ° C) with vigorous stirring is added over 30 min. 445 g of an aqueous solution of mixed potassium dithiophosphoric acid (0.93 mol) together with 15.7 g of triethylbenzylammonium chloride (68% aqueous solution) (0.0465 mol). After the addition, the reaction mixture was stirred under the same conditions for 30 min., Cooled and the crude product together with bromochloromethane separated. This was freed from bromochloromethane and volatiles by distillation under reduced pressure.

This gave 236 g of a product containing: 19.0% of O, O-diethyl S-chloromethyldithiophosphate

48.3% O-ethyl-O-isobutyl-S-chloromethyldithiophosphate

27.4% of O, O-diisobutyl-S-chloromethyldithiophosphate. The analysis was performed as in Example 1.

The total yield calculated on the starting potassium of mixed dithiophosphoric acids is 91.2%. .

Example 3

Of 244.2 g of 97.6% bromochloromethane (1.84 mol), 292 g of an aqueous solution of mixed sodium dithiophosphoric acid (0.614 mol) and 10.3 g of an aqueous solution of triethylbenzylammonium chloride (0.0307 mol) as described in Example 2, prepared 158 g of a product containing:

18.4% O.O-diethyl-SrChloromethyldithiophosphate

46.4% O-ethyl-O-isobutyl-S-chloromethyldithiophosphate

27.2% of O, O-diisobutyl-S-chloromethyldithiophosphate.

The total yield calculated on the starting salt was 90.1%.

Example 4

The product was prepared from 118.4 g of 98.4% bromochloromethane (0.9 mol), 134.7 g of an aqueous solution of mixed ammonium salts of dithiophosphoric acid (0.3 mol) and catalyst.

The catalyst used and the amount thereof, the amount of product obtained for analysis as well as yields are shown in the following table.

table

Example catalyst Protkl kt DE ⁺ Analysis in% yield (%) EIB DB 4 Triethylbenzylammonium chloride 5.02 g 68% aqueous solution 76,5 g 18.8 47.9 27.5 91.5 i ⁵ Triethylbenzylammonium chloride 10 g 68% aqueous solution 70,9 g 18.6 47.7 28.6 93.8 ⁶ Triethylbenzylammonium chloride 2.5 g 68% aqueous solution 73.2 g 14.4 44.6 27.9 80.7 7 Tetraethylammonium bromide 1.6 g 59.1 g 9.2 41.7 33.3 63.2 ⁸ N-cyclohexyl-N-ethyl-N-propargyl-N (2-bromomethyl) ammonium bromide 2.7 g .51.3 g 8.8 38.2 33.0 52.1 9 N-ethyl-N-octadecylpyrrolidinium bromide 1 g! 55,4 g 9.3 42.5 36.0 61.7 10 N-ethyl-N-dodecylmordinium bromide 2 g 68.4 g 9.2 45.6 27.5 71.4 11 1,6-hexylene-bis- (N, N-dimethyl-hexadecylammonium) dibromide 2.5 g 49,2 g 9.4 44.6 41.9 59.9 12 without catalyst 40.8 12.3 46.4 28.8 45.3

⁺ DE = 0,0-diethyl-S-chloromethyldithiophosphate ⁺⁺ EIB = O-ethyl-O-isobutyl-S-chloromethyldithiophosphate ⁺⁺⁺ DB = 0,0-diisobutyl-S-chloromethyldiphosphate

Example 13

From 247 g of bromochloromethane 97.6% (1.86 moles), 296.1 g of an aqueous solution of sodium mixed dithiophosphoric acid salts (0.621 moles) and 6.2 g of cetylpyridinium bromide, 156 g of the product were prepared according to the procedure described in Example 2. composition:

17.1% O, O-diethyl S-chloromethyldithiophosphate

45.3% O-ethyl-O-isobutyl-S-chloromethyl-dithiophosphate

27.1% O, O-diisobutyl-S-chloromethyldithiophosphate.

The total yield calculated on the salt used was 85.6%.

Example 14

From 232.2 g of bromochloromethane (1,795 moles),

465.5 g of an aqueous solution of sodium mixed dithiophosphoric salts (0.897 mol) and 14.5 g of tetrabutylammonium bromide were prepared according to the procedure of Example 2, 234 g of a product containing:

13.0% of O, O-diethyl S-chloromethyldithiophosphate

38.1% O-ethyl-O-isobutyl-S-chloromethyldithiophosphate 24.0% O, O-diisobutyl-S-chloromethyldithiophosphate.

The total yield calculated on the salt used was

74.6%.

Example 15 '

To 119 g of 97.3% bromochloromethane (0.894 mol) and 64 g of mixed dithiophosphoric acids and 5 g of triethylbenzylammonium chloride 68% aqueous solution were added at 70 ° C with vigorous stirring 11.9 g of sodium hydroxide (0.298 mol) dissolved in 65 ml of water, the procedure is the same as in Example 2. 69.6 g of the product containing

11.7% of O, O-diethyl S-chloromethyldithiophosphate

44.5% O-ethyl-6-isobutyl-S-chloromethyldithiophosphate 37.0% 0,0-diisobutyl-S-chloromethyldithiophosphate

The total yield calculated per salt used is 82.9%.

Claims (1)

3 Table 215477 Annex; Example Catalyst Pro-tkl kt DE + Analysis in (%) Yield (%) EIB DB 4 Triethylbenzylammonium chloride 5.02 g 68% aqueous solution 76.5 g 18.8 47.9 27.5 91.5 i 5 Triethylbenzylammonium chloride 10 g 68% aqueous solution 70.9 g 18.6 47.7 28.6 93.8 6 Triethylbenzylammonium chloride 2.5 g 68% aqueous solution 73.2 g 14.4 44.6 27, 9 80.7 7 Tetraethylammonium bromide 1.6 g 59.1 g 9.2 41.7 33.3 63.2 8 N-cyclohexyl-N-ethyl-N-propargyl-N- (2-bromomethyl) ammonium bromide 2 7 g, 51.3 g 8.8 38.2 33.0 52.1 9 N-ethyl-N-octadecylpyrrolidine bromide 1 g! 55.4 g 9.3 42.5 36.0 61.7 10 N-ethyl-N-dodecylmordinium bromide 2 g 68.4 g 9.2 45.6 27.5 71.4 11 1.6-hexylene- bis- (N, N-dimethyl-hexadecyl-ammonium) dibromide 2.5 g 49.2 g 9.4 44.6 41.9 59.9 12 without catalyst 40.8 12.3 46.4 28.8 45 , 3 + DE = 0,0-diethyl-S-chloromethyldithiophosphate ++ EIB = O-ethyl-O-isobutyl-S-chloromethyldithiophosphate +++ DB = 0,0-diisobutyl-S-chloromethyl diphosphate Example 13 Of 247 g bromochloromethane 97,6% (1.86 mmol), 296.1 g of an aqueous sodium dithiophosphoric acid mixed salt solution (0.621 mol) and 6.2 g of cetylpyridinium bromide were prepared according to the procedure described in Example 2, 156 g of product: 17.1% 0.0-diethyl-S -chloromethyldithiophosphate 45.3% O-ethyl-O-isobutyl-S-chloromethyldithiophosphate 27.1% 0,0-diisobutyl-S-chloromethyldithiophosphate. The total yield calculated on the salt used is 85.6%. Example 14 From 232.2 g of bromochloromethane (1.795 moles), 465.5 g of an aqueous solution of sodium mixed saltophosphoric acids (0.897 mol) and 14.5 g of GTB, 234 g of a product containing: 13.0% were prepared according to the procedure of Example 2. O-diethyl-S-chloromethyldithiophosphate 38.1% O-ethyl-O-isobutyl-S-chloromethyldithiophosphate24.0% O, O-diisobutyl-S-chloromethyldithiophosphate. The total yield calculated for the sol used was 74.6%. Example 15 11.9 g of sodium hydroxide (0.298 mol) was added to 119 g of bromochloromethane 97.3% (0.894 mmol) and 64 g of mixed dithiophosphoric acid 5 g of triethylbenzylammonium chloride at 70 ° C with vigorous stirring. dissolved in 65 ml of water, another procedure as described in Example 2. Obtaining 69.6 g of a product containing 11.7% of O, O-ethyl-S-chloromethyldithiophosphate 44.5% of O-ethyl-O-isobutyl-S- chloromethyldithiophosphate37.0% of O, O-diisobutyl-S-chloromethyldithiophosphate The total yield calculated on the salt used is 82.9%. OBJECT OF THE INVENTION A method for preparing S-chloromethyl esters of mixed dithiophosphoric acids of the formulas III-In the reaction of bromochloromethane with a mixture of dithiophosphoric acids or a mixture of their salts of the formula VIII-VIII / c2h5c / 2p-s-CK2 Cl5 i -S-CH2-C1 / i-C4Hg0 / 2 PS-CH2-C15 / C2H5fi / 2P-S-su-C4H8O / i-C4HgO / 2P-SMs y wherein M is hydrogen, ammonium, alkaline, in particular sodium or potassium, with the advantage of using excess bromochloromethane as in that the reaction takes place in an aqueous medium in the presence of a catalyst from the group of quaternary ammonium salts of the general formula (IX) Wherein R 1 is alkyl of 1 to 18 carbon atoms, R 2 is alkyl of 1 to 4 carbon atoms optionally substituted with bromine, R 3 is alkyl of 1 to 4 carbon atoms or propargyl, R 4 is alkyl of 1 to 4 carbon atoms, cyclohexyl , benzyl, 1,6-hexylene, R 1 and R 2 may together with the nitrogen quaternary ammonium salt form a 5-6 membered heterocyclic ring in which the oxygen can be an additional heteroatom, Y is a halogen of Cl, Br, J added in an amount of 1 to 10% The reaction is carried out at a temperature ranging from 20 ° C to the reflux temperature of the reaction mixture. Printed by Moravské tiskařské závodyprovoz 12, Leninova 21, Olomouc Price: 2,40 Kčs