Reference of 60186-15-4 , The common heterocyclic compound, 60186-15-4, name is 2,4-Difluoro-5-nitropyridine, molecular formula is C5H2F2N2O2, 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.
In a 50 mL round-bottomed flask vial was 2,4-difluoro-5-nitropyridine (263.4 mg, 1.645 mmol) in tetrahydrofuran (8 mL) to give a tan solution. After cooling to -40 C, 2-vinylmorpholine hydrochloride (246 mg, 1.645 mmol) was added, followed by Et3N (0.688 mL, 4.94 mmol). The cloudy tan mixture was stirred at -40 C – 0C for 5 h. TLC (1/2 EtOAc/hexane) showed little SM and one major more polar spot. The mixture was concentrated, and the residue was purified by FCC up to 60% EtOAc/hexane to afford the desired product (348 mg, 84%) as a yellow oil: 1H NMR (400 MHz, Chloroform-d) delta 8.55 (s, 1H), 6.44 (s, 1H), 6.03 – 5.88 (m, 1H), 5.38 – 5.28 (m, 1H), 5.28 – 5.17 (m, 1H), 3.98 – 3.85 (m, 4H), 3.80 (ddd, J = (0086) 11.4, 10.6, 2.8 Hz, 1H), 3.53 (ddd, J = 12.8, 10.6, 3.5 Hz, 1H), 2.95 (dtd, J = 12.9, 2.6, 0.9 Hz, 1H); 19F NMR (376 MHz, Chloroform-d) delta -61.65.
The synthetic route of 60186-15-4 has been constantly updated, and we look forward to future research findings.
Reference:
Patent; BRISTOL-MYERS SQUIBB COMPANY; LUO, Guanglin; SIVAPRAKASAM, Prasanna; DUBOWCHIK, Gene M.; MACOR, John E.; (45 pag.)WO2018/98413; (2018); A1;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem