反应详情

To a suspension of (4-methylsulfonyl)aniline (2.82 g, 16.5 mmol) in toluene (150 mL), trimethylaluminum (2M solution in toluene, 12.5 mL, 24.7 mmol) was added over 15 minutes. The reaction mixture was warmed to room temperature and stirred for 2.5 hours. A solution of piperonylonitrile (4.85 g, 33 mmol) in toluene (100 mL) was added over 10 minutes and the reaction mixture was heated to 90°-95° C. After 20 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 (2/1).The combined filtrates were concentrated in vacuo and the resulting yellowish solid was stirred with a mixture of hexane/ether (2/1, 1000 mL). The product was filtered and washed with more of hexane/ether (2/1). The pale yellow solid 3,4-methylenedioxy-N-[4-(methylsulfonyl)phenyl]benzenecarboximidamide (4.8g, 91%) was used in the next reaction without further purification: mp (DSC) 214° C. Anal. Calc'd. for C15H14N2SO4 : C, 56.59, H, 4.43, N, 8.80. Found: C, 56.33, H, 4.28, N, 8.66.

1. additionwas added over 15 minutes
2. temperaturethe reaction mixture was heated to 90°-95° C
3. waitAfter 20 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 (2/1).The combined filtrates
7. concentrationwere concentrated in vacuo
8. stirringthe resulting yellowish solid was stirred with a mixture of hexane/ether (2/1, 1000 mL)
9. filtrationThe product was filtered
10. washwashed with more of hexane/ether (2/1)
11. customThe pale yellow solid 3,4-methylenedioxy-N-[4-(methylsulfonyl)phenyl]benzenecarboximidamide (4.8g, 91%) was used in the next reaction without further purification