Hydrazine hydrate (1:1) → 1,1-Dimethylethyl 1,4,5,7-tetrahydro-6H-pyrazolo(3,4-c)pyridine-6-carboxylate

Temperature

80 °C

To a stirred mixture of tert-butyl 4-((dimethylamino)methylene)-3-oxopiperidine-1-carboxylate (1.0 g, 4 mmol) in EtOH (10 mL) was added hydrazine hydrate (376 mg, 10 mmol). The mixture was stirred at 80° C. for 16 hours until the reaction was shown to be complete by LCMS. The mixture was then concentrated and the residue was extracted with EA (3×30 mL) from water (30 mL). The combined organic extracts were washed with brine (20 mL), dried over anhydrous Na2SO4 and concentrated. The residue was directly for the next step (810 mg, 90% yield). LCMS: 224.1 (M+1), 114.1 (M+1-100), 168.1 (M+1-56).

1. concentrationThe mixture was then concentrated
2. extractionthe residue was extracted with EA (3×30 mL) from water (30 mL)
3. washThe combined organic extracts were washed with brine (20 mL)
4. dry with materialdried over anhydrous Na2SO4
5. concentrationconcentrated

ORD record

ord-c25070fb0b9e4ea4b8fc606ffe67caf7

Source dataset

uspto-grants-2016_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09388173B2