Ammonia → 3-Amino-1-(3-(trifluoromethyl)-5,6-dihydro(1,2,4)triazolo(4,3-a)pyrazin-7(8H)-yl)-4-(2,4,5-trifluorophenyl)butan-1-one

Participants

Reaction Conditions

Reaction Steps

In a 250 mL round bottom flask dry THF (56 mL) was taken. It was cooled to −10° C. and NaBH4 (1.4 g) was added. After that benzenesulfonic acid (14.6 g) dissolved in THF (20 mL) was added dropwise at −10 to 5° C. over a period of 30-60 min. 4-oxo-4-[3-(trifluoromethyl)-5,6-dihydro[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl]-1-(2,4,5-trifluorophenyl)but-2-en-2-amine (5.0 g) was mixed in a solvent mixture of THF (12.5 mL) and IPA (5.5 mL) and added into the reaction mixture, keeping the temperature between −10 to 5. It was stirred for 5 h at −10 to 0° C. Reaction mixture was poured into cold water. It was basified by adding aq. ammonia solution. Product was extracted in ethyl acetate. The organic layer was collected. It was washed with water and dried over anhydrous sodium sulfate. Solvent was evaporated at reduced pressure to obtain the product. (Wt.-5.5 g; % Y-95.6%; % Purity by HPLC-62.5%).

Provenance & Evidence