反应详情

Thionyl chloride (0.48 ml, 6.6 mmol) was added dropwise to a solution of (2R)-3-Bromo-2-hydroxy-2-methylpropionic acid (1.0 g, 5.5 mmol) in 10 ml of DMA at −5 to −10° C. The mixture was stirred for 2 h, and a solution of 3-methyl-4-nitroaniline (0.83 g, 5.5 mmol) in 7 ml of DMA was added to the above mixture. The resulting mixture was stirred for 3 h at room temperature and poured into water (250 ml). The aqueous phase was extracted with ethyl acetate (4×50 ml), dried over Na2SO4 and evaporated. The yield of the desired compound was 2.5 g (contains also DMA), and it was used without further purifications. 1H NMR (DMSO-d6): 1.48 (3H, s), 2.53 (3H, s), 3.58 (1H, d, J=10.4 Hz), 3.82 (1H, d, J=10.4 Hz), 6.34 (1H, bs), 7.86 (1H, dd, J=9.0 Hz and 2.2 Hz), 7.91 (1H, d, J=2.2 Hz), 8.04 (1H, d, J=9.0 Hz), 10.09 (1H, bs).

1. stirringThe resulting mixture was stirred for 3 h at room temperature
2. extractionThe aqueous phase was extracted with ethyl acetate (4×50 ml)
3. dry with materialdried over Na2SO4
4. customevaporated