The synthetic route of 1452-94-4 has been constantly updated, and we look forward to future research findings.
In the next few decades, the world population will flourish. As the population grows rapidly and people all over the world use more and more resources, all industries must consider their environmental impact. 1452-94-4, name is Ethyl 2-chloronicotinate, the common compound, a new synthetic route is introduced below. Safety of Ethyl 2-chloronicotinate
In a 500 ml_ dry round bottom flask with reflux condenser and magnetic stirrer was placed with 2-chloro-3-ethyl nicotinate (40.0 g, 215.5 mmol) in methanol (200 ml_). CH3ONa in methanol (25%, 65 ml_, 301.7 mmol) was added slowly and the reaction mixture was refluxed for 16 hours. The reaction was cooled to room temperature, quenched by addition of a saturated aqueous NH4CI solution. The aqueous mixture was extracted with ethyl acetate. The combined organic layers were washed well with water, brine, dried over Na2SO4 and concentrated to give 35 g of 2-methoxy-3-methyl nicotinate with 97% yield. Sodium hydride (60% in oil, 9.21 g, 230.3 mmol) was added to a dry 500 ml_ round bottom flask followed by 100 ml_ DMF. 4-Methoxyacetophenone (31.45 g, 209.44 mmol) in 50 ml_ dry DMF was added drop-wise at 00C over 30 min. The reaction mixture was stirred for 1 h at room temperature. 2-Methoxynicotinic acid methyl ester (35 g, 209.44 mmol) was dissolved in 50 ml_ dry DMF and added EPO slowly, keeping the temperature at O0C. The mixture was stirred for 16 h at room temperature, then quenched by addition of a saturated aqueous NH4CI solution and diluted with water. The solid was filtered off, washed with water and dried to give 56.7 g diketo product in 95% yield.; A solution of ethyl 2-chloronicotinitate (6.0 g, 0.0323 mol) in anhydrous methanol (10 ml_) at room temperature was added sodium methoxide (10 ml_, 25% in methanol). The reaction mixture was stirred for half hour then heated to reflux for one hour. The mixture was poured into water and extracted with ethyl acetate and the organic layer was washed with water until neutral, dried over sodium sulfate, and concentrated to give methyl 2-methoxynicotinitate (5.2 g, 96.3%).; In a 500 mL dry round bottom flask with reflux condenser and magnetic stirrer was placed with 2-chloro-3-ethyl nicotinate (40.0 g, 215.5 mmol) in methanol (200 mL), and sodium methoxide (65 mL, 301.7 mmol, 25% in methanol) was added slowly and the reaction mixture was refluxed for 16 hours. The reaction mixture was cooled to room temperature and the reaction was quenched by addition of saturated aqueous NH4CI solution, followed by extraction with ethyl acetate. The combined organic layers were washed well with water, brine, dried over Na2SO4 and concentrated to give 2-methoxy-3-methyl nicotinate (35 g, 97%). To a dry 500 mL round bottom flask was added NaH (9.21 g 230.3 mmol, 60% in mineral oil) in DMF (100 mL). 4-Methoxyacetophenone (31.45 g, 209.44 mmol) in dry DMF (50 mL) was added dropwise at 00C over 30 min. The reaction mixture was stirred for 1 h at room temperature. Then 2-methoxynicotinic acid methyl ester (35 g, 209.44 mmol) dissolved in dry DMF (50 mL) was added slowly on cooling. The mixture was stirred for 16 h at room temperature. The reaction was quenched by addition of saturated NH4CI solution and diluted with water. The solid was filtered off, washed with water and dried to give the diketo product (56.7 g, 95 %). Polyphosphoric acid (8.0 g) was heated at 900C and the diketo compound (1.0 g, 3.50 mmol) was added slowly and heated at 900C for 1 hour. The reaction mixture was cooled to room temperature and diluted with water. The solid was isolated by filtration, washed with water and dried to give 2- (4-methoxyphenyl)-4H-pyrano[2,3-b]pyridine-4-one (570 mg, 64%). MS (ES) m/z: 254.89 (M+1), 253.90 (M); MP 269-2700C.; In a 250 mL dry round bottom flask with a reflux condenser and magnetic stirrer was placed with 2-chloro-3-ethyl nicotinate (12.0 g, 64.7 mmol) in dry methanol (200 mL), and CH3ONa (21 mL, 97.0 mmol, 25% in methanol) were added slowly and the reaction mixture was refluxed for 16 hour. The reaction mixture was cooled to room temperature and quenched by addition of a saturated aqueous NH4CI solution and extracted with ethyl acetate. The combined organic layers were washed with water, brine, dried over Na2SO4 and concentrated to give 2-methoxy-3-methyl nicotinate (10.0 g, 93%). In a dry 500 mL round bottom flask NaH (549 mg, 13.7 mmol, 60% in mineral oil) was added in DMF (10 mL). Acetophenone (1.5 g, 12.5 mmol) in dry DMF (10 mL) was added drop-wise at O0C in 30 min. The reaction mixture was stirred for 1 h at room temperature. 2- Methoxy-3-m ethyl nicotinate (2.08 g, 12.5 mmol) dissolved into dry DMF (10 mL) was added slowly on cooling. After addition the mixture was stirred for 16 h at EPO room temperature. The reaction mixture was quenched by addition of a saturated aqueous NH4CI solution and diluted with water. The solid was filtered off, washed with water and dried to give the diketo product (2.94 g, 92%). Poly phosphoric acid (15.0 g) was heated at 9O0C and the diketo compound (1.5 g, 3.50 mmol) was added slowly and heated at 9O0C for 1 hours. The reaction mixture was cooled to room temperature and diluted with water. The solid was separated by filtration, washed with water and dried to give pure 2-phenyl-4H-pyrano[2,3- b]pyridin-4-one (655 mg…
The synthetic route of 1452-94-4 has been constantly updated, and we look forward to future research findings.
Reference:
Patent; RESVERLOGIX CORP.; JOHANSSON, Jan, O.; HANSEN, Henrik, C.; CHIACCHIA, Fabrizio, S.; WONG, Norman, C.W.; WO2007/16525; (2007); A2;,
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