To a stirred solution of 100 mg (0.42 mmol) 4-methoxy-7-phenyl-benzooxazol-2-ylamine, 0.087 ml (0.62 mmol) triethylamine and 5.1 mg N,N-dimethyl-4-aminopyridine in 5 ml THF at room temperature was added dropwise a solution of 0.064 ml (0.54 mmol) 4-fluoro-benzoyl chloride in 2 ml THF and stirring continued at 65° C. for 16 h. The reaction mixture was then concentrated in vacuo. To the residue was added water, and the mixture was extracted three times with dichloromethane. The combined organic phases were dried over sodium sulfate and concentrated in vacuo. Flash chromatography (1/4 then 4/1 ethyl acetate/hexane) followed by trituration in ether afforded 50 mg (33%) 4-fluoro-N-(4-methoxy-7-phenyl-benzooxazol-2-yl)-benzamide as a light yellow crystalline solid. EI-MS m/e (%): 362 (M+, 90), 123 ([FC6H4CO+, 100).
