Methanesulfonic Acid → 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

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Reaction Steps

In a 250 mL round bottom flask THF (110 mL) was taken. It was cooled to less than −5° C. and NaBH4 (2.81 g) was added. After that methanesulfonic acid (17.8 g) was added dropwise at less than −5° C. over a period of 1 h. 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 (10.0 g) is mixed in a solvent mixture of THF (25 mL) and IPA (11 mL) and added into the reaction mixture, keeping the temperature below 0° C. It was stirred for 4-6 h below 5° C. After usual work-up procedure, product was extracted in a suitable solvent. Extract was washed and dried over anhydrous sodium sulfate. Solvent was evaporated at reduced pressure to obtain the product. (Wt.-9.5 g, % Y-94.5%, % Purity by HPLC-94.6%).

Provenance & Evidence