Application of 71902-33-5 , The common heterocyclic compound, 71902-33-5, name is 3,5-Difluoropyridine, molecular formula is C5H3F2N, 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.
Step 1;To a solution of 3,5-difluoropyridine (5.4 g, 46.8 mmol, 1 eq.) in MeOH (45 mL) was added NaOMe (7.5 g, 140.4 mmol). The mixture was divided into three microwave tubes and individually heated at 135 C. for 1 h in a microwave reactor. The three tubes were combined, concentrated, and diluted with a mixture EtOAc (100 mL) and brine (30 mL). The organic layer was dried over Na2SO4 and concentrated. The crude was re-dissolved in MeOH (45 mL) and added NaOMe (7.5 g, 140.4 mmol). The mixture was again divided into three microwave tubes and individually heated at 135 C. for 1 h in a microwave reactor. The three tubes were combined and concentrated. The crude was dissolved in a mixture of EtOAc (200 mL) and brine (30 mL). The organic layer was dried over Na2SO4, concentrated, and purified on silica gel using a mixture of EtOAc and hexanes as eluent to give 3,5-dimethoxypyridine (3.73 g, 57%) as an off-white solid. 1H NMR (400 MHz, CDCl3) delta 7.98 (d, J=2.4 Hz, 2H), 6.76 (t, J=2.4 Hz, 1H), 3.88 (s, 6H). LRMS (M+H+) m/z 140.1.
The synthetic route of 71902-33-5 has been constantly updated, and we look forward to future research findings.
Reference:
Patent; Global Blood Therapeutics, Inc.; The Regents of the University of Califorina; Cytokinetics, Inc.; Metcalf, Brian; Chuang, Chihyuan; Warrington, Jeffrey; Paulvannan, Kumar; Jacobson, Matthew P.; Hua, Lan; Morgan, Bradley; US2015/344483; (2015); A1;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem