反应详情

温度

0 °C

To a solution of (R,E)-2-methyl-N-(4-(trifluoromethoxy)benzylidene)propane-2-sulfinamide (7.7 g, 26.3 mmol) in CH2Cl2 (150 mL), cooled to 0° C. (water/ice bath), under nitrogen, was added 3M methyl magnesium bromide (35 mL, 105 mmol) in Et2O. The reaction mixture was stirred at 0° C. for 30 min, then allowed to warm up to room temperature and stirred additional 4 hrs. The reaction mixture was cooled again to 0° C. and quenched with the slow addition of a saturated NH4Cl solution. The by-phasic mixture was diluted with DCM and Water and the aqueous extracted with DCM two times. The organic phases were combined, washed with brine, dried (Na2SO4), filtered and concentrated to 11.5 g crude white solid. Silica gel column chromatography (EtOAc/Heptane 0 to 30%) afforded (R)-2-methyl-N—((S)-1-(4-(trifluoromethoxy)phenyl)ethyl)propane-2-sulfinamide (5.08 g, 16.2 mmol, 62% yield) as a white crystalline solid. 1H NMR (400 MHz, CDCl3) δ 1.21 (s, 9H) 1.53 (d, J=6.70 Hz, 3H) 3.31 (d, J=2.74 Hz, 1H) 4.59 (qd, J=6.67, 3.37 Hz, 1H) 7.18 (d, J=8.02 Hz, 2H) 7.36 (d, J=8.66 Hz, 2H). LCMS m/z 310.2 (M+H)+, Rt 0.90 min.

1. temperatureto warm up to room temperature
2. stirringstirred additional 4 hrs
3. temperatureThe reaction mixture was cooled again to 0° C.
4. customquenched with the slow addition of a saturated NH4Cl solution
5. additionThe by-phasic mixture was diluted with DCM and Water
6. extractionthe aqueous extracted with DCM two times
7. washwashed with brine
8. dry with materialdried (Na2SO4)
9. filtrationfiltered
10. concentrationconcentrated to 11.5 g crude white solid