反应详情

To a solution of 0.23 g N-ethyl-2,3-diaza-spiro[4.4]non-3-ene-2-carboxamidine in 5 mL dry DMF was added 0.87 mL (3.0 equiv.) BEMP and the light brown mixture was stirred for 10 minutes at room temperature. Subsequently, 0.33 g (1.1 equiv.) 3-methyl-4-(2,2,2-trifluoro-acetylamino)-benzenesulfonyl chloride was added in one portion and the resulting bright yellow solution was stirred overnight at room temperature. The mixture was cooled in an ice bath, acidified with 1 N HCl, and then extracted three times with EtOAc/Et2O 1:1. The combined organic layers were washed once with water, then with brine, dried over Na2SO4 and evaporated onto silica. Purification with flash chromatography (EtOAc/PA 4:6→5:5) yielded 0.18 g (39%) of a white solid. 1H NMR (400 MHz, CDCl3) δ 1.16 (t, J=7.2 Hz, 3H), 1.63-1.86 (m, 8H), 2.33 (s, 3H), 3.43-3.52 (m, 2H), 3.83 (s, 2H), 6.77-6.85 (br.s., 1H), 6.83 (s, 1H), 7.73-7.79 (m, 2H), 7.86 (d, J=8.3 Hz, 1H), 8.10 (br.s., 1H).

1. stirringthe resulting bright yellow solution was stirred overnight at room temperature
2. temperatureThe mixture was cooled in an ice bath
3. extractionextracted three times with EtOAc/Et2O 1:1
4. washThe combined organic layers were washed once with water
5. dry with materialwith brine, dried over Na2SO4
6. customevaporated onto silica
7. customPurification with flash chromatography (EtOAc/PA 4:6→5:5)