Related Products of 3149-28-8,Some common heterocyclic compound, 3149-28-8, name is 2-Methoxypyrazine, molecular formula is C5H6N2O, 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.
Representative procedure for the preparation of 1-phenoxycarbonyl-2-phenyl-3-methoxy-1,2-dihydropyrazine (3a). To a stirred solution of 2-methoxypyrazine (0.200 g, 1.816 mmol) inanhydrous THF (5 mL) was added phenylchloroformate (0.28 mL, 2.225 mmol) at 0 C andstirring was continued under nitrogen atmosphere until salt formation was completed (15 min, asdetermined by TLC on neutral alumina, EtOAc/hexanes 1:19). The reaction mixture was cooledto -41 C, a 1 M solution of phenylmagnesium bromide in THF (2.4 mL, 2.4 mmol) was addedand the mixture stirred until reaction completion (40 min, as determined by TLC on neutral SiO2,EtOAc/hexanes 1:9), and then quenched with 2 mL of aqueous 20% NH4OH/NH4Cl 1:1 (w/w).The mixture was extracted with dichloromethane (2 × 15 mL), dried over Na2SO4, andconcentrated in vacuo. Purification of the crude mixture by flash silica gel columnchromatography (0-15% EtOAc/hexanes) afforded 3a (0.488 g, 87%) as a white solid (3:2mixture of rotamers): mp: 81-82 C; 1H NMR (CDCl3, 500 MHz) delta 7.49-7.27 (m, 7H), 7.20 (t, J= 7.5 Hz, 1H), 7.12 (d, J = 8.0 Hz, 1H), 6.99 (d, J = 7.5 Hz, 1H), 6.67 and 6.63 (2d due torotamers, J = 5.5 Hz, 1H), 6.16 and 6.14 (2d due to rotamers, J = 5.0 Hz, 1H), 5.89 and 5.87 (2sdue to rotamers, 1H), 3.84 and 3.83 (2s due to rotamers, 3H); 13C NMR (CDCl3, 125 MHz) delta160.2, 160.0, 151.6, 151.5, 150.7, 150.4, 136.8, 135.9, 129.3, 128.8, 128.7, 128.6, 127.2, 126.6,125.9, 125.8, 121.3, 118.2, 118.1, 112.5, 111.8, 56.0, 54.6, 54.0, 53.9; HRMS (ESI) m/z calcdfor C18H17N2O3 [M + H]+ 309.12337, found 309.123554
The synthetic route of 3149-28-8 has been constantly updated, and we look forward to future research findings.
Reference:
Article; St Hilaire, Valentine R.; Hopkins, William E.; Miller, Yenteeo S.; Dandepally, Srinivasa R.; Williams, Alfred L.; Beilstein Journal of Organic Chemistry; vol. 15; (2019); p. 72 – 78;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem