反应详情

To a suspension of 4-fluoroaniline (4 mL, 40 mmol) in toluene (120 mL), trimethylaluminum (2M solution in toluene, 21 mL, 42 mmol) was added over 15 minutes. The reaction mixture was warmed to room temperature and stirred for 3 hours. A solution of 4-(methylsulfonyl)benzonitrile (7.65 g, 40 mmol) in methylene chloride (100 mL) was added over 10 minutes and the reaction mixture was heated to 70-75° C. After 48 hours, the reaction mixture was cooled to room temperature and poured over a slurry of silica gel in chloroform. After filtration, the residue was washed with a mixture of methylene chloride/methanol. The combined filtrates were concentrated in vacuo and the resulting crude intermediate (7.7 g) was purified by chromatography [silica gel, hexane/ethyl acetate, 25/75] to give 4-methylsulfonyl-N-[4-chlorophenyl]benzenecarboximidamide (4.1 g, 35%) as a white solid: mp (DSC) 182° C. Anal. Calc'd. for C14H13N2SO2F: C, 57.52, H, 4.48, N, 9.58, S, 10.97. Found: C, 57.37, H, 4.69, N, 9.21, S, 10.69.

1. additionwas added over 15 minutes
2. temperaturethe reaction mixture was heated to 70-75° C
3. waitAfter 48 hours
4. temperaturethe reaction mixture was cooled to room temperature
5. filtrationAfter filtration
6. washthe residue was washed with a mixture of methylene chloride/methanol
7. concentrationThe combined filtrates were concentrated in vacuo
8. customthe resulting crude intermediate (7.7 g) was purified by chromatography [silica gel, hexane/ethyl acetate, 25/75]