Reference of 22353-40-8 , The common heterocyclic compound, 22353-40-8, name is 2,3-Dichloro-5-nitropyridine, molecular formula is C5H2Cl2N2O2, 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.
Example 2C 5-amino-2,3-dichloropyridine Anhydrous SnCl2 (300 g, 1.58 mol) and concentrated HCl (350 mL) were charged to a 5 L flask with mechanical stirrer and thermocouple. The flask was cooled in ice and the product of Example 2B (100 g, 0.518 mol) was added in portions maintaining the temperature below 65 C. After the addition was complete, the cold bath was removed, and the mixture was stirred for 2 hours at ambient temperature. The mixture was cooled in ice as 25% aqueous NaOH (1000 mL) was added to bring the mixture to pH>10. The mixture was extracted with CH2Cl2 (1*600 mL, 2*400 mL) and the combined extracts were washed with brine (200 mL), dried (MgSO4), and concentrated under vacuum. The residual solid was crystallized from a mixture of water (500 mL) and ethanol (100 mL) to provide the title compound as a solid. 1H NMR (CDCl3, 300 MHz) delta 3.80 (br s, 2H), 7.10 (d, J=3 Hz, 1H), 7.77 (d, J=3 Hz, 1H); MS (DCI/NH3) m/Z 180/182/184 (M+NH4)+163/165/167 (M+H)+.
The synthetic route of 22353-40-8 has been constantly updated, and we look forward to future research findings.
Reference:
Patent; Buckley, Michael J.; Ji, Jianguo; US2005/261348; (2005); A1;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem