反应详情

The methyl 6-(benzyloxycarbonylamino)picolinate from step 1 was dissolved in ethanol (0.5 M), and hydrazine hydrate (15 mL, 310 mmol, 5.0 eq) was added. The solution was heated to reflux and stirred for 2 hours, then cooled to room temperature. The solvent was removed under reduced pressure to provide a yellow solid, which was suspended in acetonitrile, filtered, and the solid washed with acetonitrile to yield benzyl 6-(hydrazinocarbonyl)pyridin-2-ylcarbamate (17.5 g) as a white solid. The filtrate was concentrated and the precipitated solid filtered off and washed with acetonitrile to provide more benzyl 6-(hydrazinecarbonyl)pyridin-2-ylcarbamate. A total of 17.5 g of pure material was obtained.

1. temperatureThe solution was heated
2. temperatureto reflux
3. customThe solvent was removed under reduced pressure
4. customto provide a yellow solid, which
5. filtrationfiltered
6. washthe solid washed with acetonitrile