反应详情

Anhydrous tetrahydrofuran (250 ml) was added to (2R)-2-(3,4,5,6-tetrahydro-2H-pyran-2-yloxy)propionic acid (32 g). To the mixture was added by portions 1,1'-carbonyl-diimidazole (35.8 g), with stirring at room temperature during 10 minutes. The resultant mixture was stirred for 30 minutes at room temperature and, then, cooled with ice, to which was added dropwise morpholine (38.3 g) during 15 mintues, followed by stirring for 15 minutes in an ice-bath. The reaction mixture was concentrated under reduced pressure, and the concentrate was dissolved in dichloromethane (300 ml). The solution was washed with a saturated aqueous solution of sodium chloride (50 ml) and dried over anhydrous magnesium sulfate, followed by distilling off the solvent. The residue was purified by means of a silica gel chromatography (eluent: hexane-ethyl acetate=1:4) to afford N-[(2R)-2-(3,4,5,6-tetrahydro-2H-pyran-2-yloxy)propionyl]morpholine (25.7 g).

1. temperaturecooled with ice, to which
2. stirringby stirring for 15 minutes in an ice-bath
3. concentrationThe reaction mixture was concentrated under reduced pressure
4. dissolutionthe concentrate was dissolved in dichloromethane (300 ml)
5. washThe solution was washed with a saturated aqueous solution of sodium chloride (50 ml)
6. dry with materialdried over anhydrous magnesium sulfate
7. distillationby distilling off the solvent
8. customThe residue was purified by means of a silica gel chromatography (eluent: hexane-ethyl acetate=1:4)