反应详情

A solution of 1-methyl-4-phenyl-4-piperidinol (7.65 g, 40 mM), in DMSO (100 ml) was treated with 50% sodium hydride dispersion (2.0 g, 40 mM) and the mixture warmed to 80° until a clear solution was obtained. After cooling to room temperature a solution of 2-chloropyrazine (5.6 g, 40 mM) in DMSO (10 ml) was added. After 48 hours the reaction mixture was poured on to water (400 ml), extracted with ether (3×250 ml), the organic phase dried and the solvents removed under reduced pressure. Recrystallisation of the residue from cyclohexane gave recovered 1-methyl-4-phenyl-4-piperidinol (2 g). Chromatography of the mother liquors on Grade III silica using 3% methanol in chloroform as eluant, evaporation of the appropriate fractions and recrystallisation from pentane gave the title compound (1.2 g) m.p. 115°-6° C.

1. temperaturethe mixture warmed to 80° until a clear solution
2. customwas obtained
3. additionwas added
4. extractionextracted with ether (3×250 ml)
5. customthe organic phase dried
6. customthe solvents removed under reduced pressure
7. customRecrystallisation of the residue from cyclohexane
8. customgave
9. customrecovered 1-methyl-4-phenyl-4-piperidinol (2 g)
10. customChromatography of the mother liquors on Grade III silica using 3% methanol in chloroform as eluant, evaporation of the appropriate fractions and recrystallisation from pentane