Preparation and application of pyrimisulfuron-methyl_Kain Industrial Additives

Background and overview^[1][2]

Orthosulfamuron is a pyrimidine sulfonylurea herbicide reported by the Italian company Isagro in 1998 and jointly developed by Isagro and RiceCo. It is used in pre-emergence and post-emergence applications. Control sedges and grass weeds in rice fields. In 2007, it was first registered and sold in the United States under the trade name Strada for weeding in rice fields. In 2011, it was registered in China for the control of barnyard grass, sedges and broadleaf weeds in rice fields. Its effect is obvious, its performance is excellent, and it has broad application prospects. It is believed that it will be widely used in our country in the next few years.

Preparation^[1]

Using anthranilic acid and 2-amino-4,6-dimethoxypyrimidine as starting materials, the target compound pyrimidinesulfuron-methyl was prepared through a total of 4 steps (see Figure 1),

1.2 Synthesis of isatoic anhydride (compound M-2)

Put 13.7 g (0.1 mol) anthranilic acid (M- 1) into a 250 mL reaction bottle, add 80 mL tetrahydrofuran, slowly add 14.8 g (0.05 mol) solid phosgene at 0°C, and slowly increase to room temperature, stir and react for 1 hour, raise the temperature and reflux for 4 hours, and monitor the reaction with TLC to complete. Remove the solvent under reduced pressure and add 20 mL

Tetrahydrofuran and 20 mL of water were stirred for 5 min, and filtered to obtain 15.2 g of white solid (M-2), with a crude yield of 93.3%.

1.3 Synthesis of 2-amino-N,N-dimethylphenylamide (compound M-3). Take 14.7 g (0.09 mol) isatoic anhydride (M- 2) in a 250 mL reaction bottle, and add 80 mL Tetrahydrofuran, slowly add 25.0 g (0.18 mol) of 33% dimethylamine aqueous solution dropwise with stirring at room temperature, complete the dropwise addition in 1 hour, continue the reaction overnight, and monitor the reaction with TLC to complete. Remove the solution under reduced pressure, add ethyl acetate and water for extraction, dry the organic layer, and remove the solution under reduced pressure to obtain 13.5 g of light brown solid, with a crude yield of 91.5%.

1.4 Synthesis of 4,6-dimethoxypyrimidine-2-carbamoylsulfonyl chloride (compound M-5)

4.3 g (30.5 mmol) sulfonyl chloride isocyanate dissolved in dichloromethane (10 mL) was dropped into 5.2 g (33.6 mmol) 2-amino-4,6-dimethoxypyrimidine at 0 °C. In methyl chloride (50 mL) solution, the reaction was stirred at this temperature for 1 h. TLC monitored the reaction and was used directly in the next reaction without treatment.

1.5 Synthesis of pyrimisulfuron-methyl

A solution of 5.0 g (30.5 mmol) 2-amino-N,N-dimethylphenylamide (compound M-3) and 3.1 g (30.6 mmol) triethylamine in dichloromethane (20 mL) was slowly added. Slowly add the solution obtained in the previous step (compound 5), stir at 0°C for 10 min, and then stir at room temperature for 4 h. TLC monitors the reaction to be completed. Pour the reaction solution into dilute hydrochloric acid and saturated brine, extract with dichloromethane, dry the organic phase, and desolubilize to obtain 9.0 g of white solid (yield 69.5%, content 98%), melting point 159~161°C, literature report 160~ 162°C. ¹H NMR (300 MHz, DMSO) δ: 12.19 (s, 1H, NH), 10.51 (s, 1H, NH), 9.49 (s, 1H, NH) ), 7.22～7.48(m, 4H, Ph- 4H), 5.87(s, 1H, Py- 5- H), 3.82(s, 6H, 2OCH3), 2.98(s, 3H, NCH3), 2.85(s, 3H, NCH3).

Apply^[2-4]

CN201410693115.3 discloses a product containing pyrimidinesulfuron andThe pesticide composition of pyrimidine and pyrimidine includes active ingredients pyrimidine and pyrimidine, and the rest are pesticide auxiliaries. The mass ratio of pyrimidine and pyrimidine is 1:10~10: 1. The mass percentage of the sum of the mass of pyrimisulfuron-methyl and pyrimidinoximefen in the pesticide composition is 3% to 92%; according to application needs, the present invention can be prepared into dispersible oil suspensions, suspending agents, wettable powders, One of the water-dispersible granules, it is used to control annual weeds in transplanted rice fields; the pesticide composition of the present invention is significantly more effective in controlling annual weeds in transplanted rice fields than any single agent, reducing the dosage of pesticides and delaying weed resistance. .

CN201610635501.6 discloses a herbicidal composition containing pyrimasulfuron-methyl and cyhalofop-ethyl. The active ingredients are pyrimidinesulfuron-methyl and cyhalofop-ethyl, and the weight parts of pyrimidinesulfuron-methyl and cyhalofop-ethyl are The number ratio is 10:1 to 1:10; the herbicidal composition of the present invention is significantly more effective in preventing and controlling annual weeds in rice fields than a single agent, reducing the dosage of pesticides and reducing the adverse impact of pesticides on the ecological environment. , which is of great significance for the comprehensive management of weed resistance and has huge economic and social benefits.

CN201410138571.1 relates to a herbicidal composition containing oxatrione and pyrimasulfuron-methyl, the active ingredients of which are oxatrione and pyrimisulfuron-methyl, and the weight ratio of the two is 10:1~ 1:10, the better ratio is 5:1~1:3. The weight percentage of the sum of the weights of clomatrione and pyrosulfuron-methyl in the pesticide composition is 0.1% to 85%. The herbicidal composition has a synergistic effect. Compared with the use of a single agent alone, the herbicidal composition significantly improves the herbicidal effect, expands the herbicidal spectrum, reduces the amount of pesticides used, reduces environmental pollution, and delays the development of weed resistance. It is produced and mainly used to control annual weeds in rice fields.

Main reference materials

[1] Chai Baoshan, Sun Xufeng, Cui Dongliang, Liu Changling. Synthesis and biological activity of pyrosulfuron-methyl [J]. Pesticides, 2015, 54(01):14-15.

[2] CN201410693115.3 A pesticide composition containing pyrimisulfuron and pyrimidinoximefenfen

[3] CN201610635501.6 A herbicidal composition containing pyrimidine and cyhalofop-ethyl

[4] CN201410138571.1 A herbicidal composition containing oxatrione and pyrosulfuron-methyl