Diisopropylethylamine → 4-[[3-(6,8-dihydro-5H-[1,2,4]triazolo[1,5-a]pyrazine-7-carbonyl)-4-fluoro-phenyl]methyl]-2H-phthalazin-1-one

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Reaction Steps

2-Fluoro-5-[(4-oxo-3H-phthalazin-1-yl)methyl]benzoic acid 1a (360 mg, 1.20 mmol) was dissolved in 10 mL of N,N-dimethylformamide, followed by addition of O-(1-benzotriazolyl)-N,N,N′,N′-tetramethyluronium hexafluorophosphate (600 mg, 1.80 mmol), 5,6,7,8-tetrahydro-[1,2,4]triazolo[1,5-a]pyrazine 16a (150 mg, 1.20 mmol, prepared according to a known method disclosed by “patent application WO2009090055”) and N,N-diisopropylethylamine (0.4 mL, 2.40 mmol). After stirring for 20 hours, the reaction mixture was concentrated under reduced pressure and the resulting residue was purified by thin layer chromatography with elution system A to obtain 4-[[3-(6,8-dihydro-5H-[1,2,4]triazolo[1,5-a]pyrazine-7-carbonyl)-4-fluoro-phenyl]methyl]-2H-phthalazin-1-one 16 (100 mg, yield 21.0%) as a yellow solid.

Provenance & Evidence