Phosphorus oxychloride → 5-[3,5-bis(trifluoromethyl)benzyl]-9-chloro-6-oxo-7-phenyl-2,3,4,5-tetrahydro-6H-pyrido[2,3-b][1,5]oxazocine

Participants

Reaction Steps

5-[3,5-Bis(trifluoromethyl)benzyl]-6-oxo-7-phenyl-2,3,4,5-tetrahydro-6H-pyrido[2,3-b][1,5]oxazocine 10-oxide (compound of Reference Example 10; 400 mg) was added to phosphorus oxychloride (1.5 mL), and the mixture was refluxed for 1 hour while heated. The solvent was removed by distillation to obtain a residue. To this residue, ethyl acetate was added, and then the resulting crystals were collected. As a result, 5-[3,5-bis(trifluoromethyl)benzyl]-9-chloro-6-oxo-7-phenyl-2,3,4,5-tetrahydro-6H-pyrido[2,3-b][1,5]oxazocine was obtained (440 mg, 99%).

Provenance & Evidence