Pyridine → (6R,9aR)-1,1-dimethyl-6-(3,4,5-trifluorophenyl)tetrahydro [1,4]oxazino[3,4-c][1,4]oxazine-3,4-dione

Participants

Reaction Steps

To a solution of 2-[(3R,5R)-5-(3,4,5-trifluorophenyl)morpholine-3-yl]propane-2-ol (330 mg) and pyridine (2 mL) in chloroform (10 mL) was dropwise added oxalyl chloride (205 μL) while cooling with ice. The resultant solution was stirred at the same temperature for 1 hour, and then stirred for another 2 hours at room temperature. The resultant solution was diluted with water, and the organic layer was partitioned. The organic layer was washed with brine and then dried over anhydrous magnesium sulfate. Solvent was removed by distillation under reduced pressure. The resultant residue was purified by silica gel column chromatography (heptane/ethyl acetate), to thereby obtain the titled compound (260 mg). The physical properties of this crude product were as follows.

Provenance & Evidence