Aluminium lithium hydride → 4,5,6,7-Tetrahydro-5-(phenylmethyl)-pyrazolo[1,5-a]pyrazine-2-methanol

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Reaction Steps

A 1M solution of lithium aluminum hydride in THF (6.5 mL, 6.5 mmol) was added dropwise to a stirred solution of 4,5,6,7-tetrahydro-4-oxo-5-(phenylmethyl)-pyrazolo[1,5-a]pyrazine-2-carboxylic acid ethyl ester (0.81 g, 2.7 mmol) in THF (16 mL) under N2 at 0° C. The reaction mixture was stirred at room temperature for 30 minutes, quenched with MeOH and the solvents evaporated in vacuo. The crude product was purified by flash column chromatography (silica; 7 M solution of ammonia in methanol in DCM 0/100 to 10/90). The desired fractions were collected and the solvents evaporated in vacuo to yield 4,5,6,7-tetrahydro-5-(phenylmethyl)-pyrazolo[1,5-a]pyrazine-2-methanol (0.67 g, 100% yield) as a colorless oil. C14H17N3O LCMS: Rt 1.25, m/z 244 [M+H]+ (see LCMS Method 1).

Provenance & Evidence