反应详情

To the stirred ethyl acetate solution of 5-(2-chlorophenyl)-2H-pyrazol-3-ylamine was added the ethyl acetimidate free base solution over 10 minutes. Glacial acetic acid (140 ml, 2.42 mol) was then added over a 20-minute period while maintaining the reaction between 10 and 30° C. A precipitate began to form after approximately 15 ml of acetic acid had been added. After stirring for 5 hours, the product was collected on a course sintered glass funnel. The product on the filter was washed with ethyl aceate until the eluent was colorless. After drying overnight on the frit under a stream of air using low vacuum, intermediate I-1A-1a was obtained as an off-white, crystalline solid (543 g, 82.6%): +ESI MS (M+1) 235.1; 1H NMR (400 MHz, CD3OD) δ 7.58-7.52 (m, 2H), 7.42-7.39 (m, 2H), 6.43 (s, 1H), 2.38 (s, 3H), 1.86 (s, 3H).

1. temperaturewhile maintaining
2. customthe reaction between 10 and 30° C
3. additionhad been added
4. customthe product was collected on a course sintered glass funnel
5. washThe product on the filter was washed with ethyl aceate until the eluent
6. customAfter drying overnight on the frit under a stream of air