These common heterocyclic compound, 109838-85-9, name is (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine, 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. Safety of (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine
General procedure: Butyl lithium (1.6 N solution in hexane, 1.05 equiv) was added to a solution of (2R)-1 (1 equiv) in anhydrous THF (5 mL) cooled to ?78°C, and the mixture was stirred for 45 min. Imine 2a?f (1 equiv) in THF (4 mL) was added, and the mixture was stirred at ?78°C for 8h. The reaction mixture was allowed to warm to ?10 °C, after which a pH=7 phosphate buffer solution (10 mL) was added, and the mixture was extracted with ethyl acetate (3×10 mL). The organic phase was separated and dried with Na2SO4, and the solvent was evaporated in vacuo. Compounds 3, 4 were purified by means of flash chromatography (SiO2, CH2Cl2/hexane=40/60 for 3a (Rf 0.2) and 4a (Rf 0.4); CH2Cl2/ethyl acetate=95/5 for 3d (Rf 0.4) and 4d (Rf 0.5), 3e (Rf 0.5) and 4e (Rf 0.6); CH2Cl2/ethyl acetate=98/2 for 4f (Rf 0.6)).
The synthetic route of (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine has been constantly updated, and we look forward to future research findings.
Reference:
Article; Cremonesi, Giuseppe; Dalla Croce, Piero; Gallanti, Maddalena; La Rosa, Concetta; Tetrahedron; vol. 70; 11; (2014); p. 2054 – 2058;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem