反应详情

温度

-76 °C

In a round-bottomed flask, (S)-2-methyl-propane-2-sulfinic acid 1-(3-trifluoromethoxyphenyl)-meth-(E)-ylideneamide (424 mg, 1.45 mmol) was dissolved in THF (2.9 ml). The light yellow solution was cooled to −76° C. and methylmagnesium bromide (3.0 M in diethyl ether, 0.86 ml, 2.58 mmol) was added dropwise. The reaction mixture was allowed to warm slowly to room temperature overnight then quenched with saturated aqueous NH4Cl and extracted with EtOAc (2×). The combined organic layers were washed with water and brine then dried over sodium sulfate, filtered and concentrated. The residue was chromatographed over silica gel with EtOAc/hexanes (gradient: 0-10% EtOAc) to give 225 mg (50%) of (S)-2-methyl-propane-2-sulfinic acid [(R)-1-(3-trifluoromethoxy-phenyl)-ethyl]-amide as a colorless oil. 1H NMR (CDCl3, 400 MHz): δ (ppm) 7.33-7.41 (m, 1H), 7.24-7.28 (m, 1H), 7.22 (s, 1H), 7.13 (dd, J=8.1, 1.0 Hz, 1H), 4.62 (q, J=6.7 Hz, 1H), 1.55 (d, J=6.6 Hz, 3H), 1.22 (s, 9H). Also isolated 161 mg (36%) of (S)-2-methyl-propane-2-sulfinic acid [(S)-1-(3-trifluoromethoxy-phenyl)ethyl]-amide as a colorless oil. 1H NMR (CDCl3, 400 MHz): δ (ppm) 7.35-7.43 (m, 1H), 7.28-7.33 (m, 1H), 7.21 (s, 1H), 7.11-7.18 (m, 1H), 4.58 (qd, J=6.4, 2.9 Hz, 1H), 1.53 (d, J=6.6 Hz, 3H), 1.25 (s, 9H).

1. temperatureto warm slowly to room temperature overnight
2. customthen quenched with saturated aqueous NH4Cl
3. extractionextracted with EtOAc (2×)
4. washThe combined organic layers were washed with water and brine
5. dry with materialthen dried over sodium sulfate
6. filtrationfiltered
7. concentrationconcentrated
8. customThe residue was chromatographed over silica gel with EtOAc/hexanes (gradient: 0-10% EtOAc)