反应详情

温度

42.5 °C

In a 50 mL three neck flask IPA (5 mL), water (2 mL) and Dibenzoyl-L-tartaric acid monohydrate (1.84 g) were taken. It was heated to 40-45° C. 4-oxo-4-[3-(trifluoromethyl)-5,6-dihydro[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl]-1-(2,4,5-trifluorophenyl)butan-2-amine (2.0 g, % purity-94%) dissolved in IPA (5 mL) was added into reaction mixture at 60-65° C. It was stirred for 1 h at 60-65° C. It was gradually cooled to room temperature. Then it was further cooled to 0-5° C. and stirred for 1 h. The salt was filtered and washed with cold IPA. An enantiomerically enriched desired Dibenzoyl-L-tartaric acid salt of mixture of (2R) and (2S)-4-oxo-4-[3-(trifluoromethyl)-5,6-dihydro[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl]-1-(2,4,5-trifluorophenyl)butan-2-amine was obtained (Wt.-1.1 g, % Y-28.7%, Purity by HPLC-99.1%, % Chiral purity by HPLC of R-isomer 74%).

1. additionwas added into reaction mixture at 60-65° C
2. temperatureIt was gradually cooled to room temperature
3. temperatureThen it was further cooled to 0-5° C.
4. stirringstirred for 1 h
5. filtrationThe salt was filtered
6. washwashed with cold IPA
7. additionAn enantiomerically enriched desired Dibenzoyl-L-tartaric acid salt of mixture of (2R)