Extended knowledge of 59782-85-3

Synthetic Route of 59782-85-3 , The common heterocyclic compound, 59782-85-3, name is 2,5-Dichloronicotinic acid, molecular formula is C6H3Cl2NO2, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc., below Introduce a new synthetic route.

Piperazine A37 may be used in place of piperazine or a substituted piperazine in the above examples. Lithium 2-amino-5-chloronicotinateA solution of 2,5-dichloronicotinic acid (20.2 g, 0.105 mol) in methanol (500 mL) was cooled to 00C and neat thionyl chloride (38 mL, 63 g, 0.525 mol) was added over -30 min. The reaction mixture was stirred at O0C for 1 hour. The cooling bath was removed, the reaction temperature was allowed to warm to room temperature, and the reaction was allowed to stir for an additional 2 days at room temperature. The solvent was removed under reduced pressure to give an off-white residue. The residue was dissolved in Et2O (-500 mL) and the resulting solution was washed successively with saturated aqueous NaHCO3 solution (-300 mL), water (-300 mL), and brine (-300 mL). The organic layer was separated, dried over anhydrous MgSO4, and filtered. Removal of the solvent under reduced pressure yielded methyl 2,5-dichloronicotinate (21.0 g, 97%) as a white solid. EPO Performed in duplicate on identical scales in two pressure vessels, methyl 2,5-dichloronicotinate (4.5 g, 22 mmol) was dissolved in ammonia solution (250 mL, 0.5 M in 1,4-dioxane; 0.125 mol). The pressure vessels were sealed and heated at (85 +/- 5) 0C for 9 days. The two reaction mixtures were allowed to cool to room temperature, then combined and concentrated under reduced pressure to yield a white solid. Dissolution of the solid in 1 :1 acetone-MeOH (-500 mL), followed by adsorption onto silica gel (25 g) and then purification by flash column chromatography (25:10:1 hexane-CH2CI2- Et2O), gave 6.08 g (75%) of methyl 2-amino-5-chloronicotinate. A solution of LiOH*H2O (1.38 g, 33 mmol) in water (33 mL) was added in one portion to a suspension of methyl 2-amino~5~chloronicotinate (6.08 g, 27 mmol) in MeOH (110 mL). The reaction mixture was stirred at 7O0C for 24 hours, and gradually became homogeneous. The solvents were removed under reduced pressure, and after the resulting white solid was dried under vacuum (<1 mmHg) to constant weight, 5.51 g (95%) of lithium 2-amino-5-ch.oronicotinate was obtained. The synthetic route of 59782-85-3 has been constantly updated, and we look forward to future research findings. Reference:
Patent; SCHERING CORPORATION; PHARMACOPEIA DRUG DISCOVERY, INC.; WO2006/88840; (2006); A1;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem