Reference of 1480-65-5 , The common heterocyclic compound, 1480-65-5, name is 5-Chloro-2-fluoropyridine, molecular formula is C5H3ClFN, 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.
To a suspension of 5-chloro-2-fluoropyridine 4d (5.00g, 38.0mmol) and guanidine carbonate (20.5g, 114mmol) in NMP (50mL) was added K2CO3 (26.3g, 190mmol), and the mixture was heated to 130°C and stirred for 8h. To the mixture at room temperature were added EtOAc (100mL) and H2O (200mL), and the layers were separated. The aqueous layer was extracted with EtOAc (3×100mL), and the combined organic layer was washed with 10percent aqueous NaCl (3×50mL) and concentrated in vacuo. To the resulting residue was added EtOAc (500mL), and the solution was filtered through a pad of NH silica gel. The filtrate was evaporated, and the residue was suspended in EtOAc/ hexane (1:3, 40mL). The mixture was stirred at 40°C for 1h. The mixture was cooled to room temperature and stirred for 1h, and then filtered. The obtained solids were dissolved into H2O (15mL) at 50°C, and the solution was gradually cooled to room temperature. The slurry was stirred at room temperature for 1h, and then filtered to give 5d (3.03g, 47percent) as a white solid. Mp 162?163°C; 1H NMR (500MHz, DMSO-d6) delta 6.60 (dd, J=8.8, 0.6Hz, 1H), 6.75 (br s, 4H), 7.48 (dd, J=8.8, 2.8Hz, 1H), 8.04 (d, J=2.5Hz, 1H); 13C NMR (125MHz, DMSO-d6) delta 119.3, 120.0, 136.5, 143.7, 157.6, 162.1; IR (ATR) 3468, 3414, 2362, 1627, 1573, 1543, 1518, 1463, 1370, 1314, 1278, 1229, 1133, 1110, 1004, 914, 857, 834, 756, 730, 614, 572, 520, 459, 436, 405cm?1; HRMS-ESI (m/z): [M+H]+ calcd for C6H8ClN4 171.0437; found, 171.0432.
The synthetic route of 1480-65-5 has been constantly updated, and we look forward to future research findings.
Reference:
Article; Ishimoto, Kazuhisa; Nagata, Toshiaki; Murabayashi, Mika; Ikemoto, Tomomi; Tetrahedron; vol. 71; 3; (2015); p. 407 – 418;,
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