Dimethylformamide → 1,1-Dimethylethyl 2-{[6-(methyloxy)-2-pyridinyl]carbonyl}hydrazinecarboxylate

Temperature

0 °C

A solution of 6-(methyloxy)-2-pyridinecarboxylic acid (1.00 g, 6.53 mmol) in dichloromethane (DCM) (13.52 ml) was stirred and cooled to 0° C. Oxalyl chloride (0.686 ml, 7.84 mmol) was added dropwise followed by DMF (5.06 μl, 0.065 mmol). The solution immediately turned yellow and the reaction was followed by LCMS. LCMS after circa 1 hour showed the methyl ester of the acid chloride to be present. The solvent was removed under reduced pressure and the residue was azeotroped with toluene. The residue was dissolved in dichloromethane (DCM) (27.0 ml) and cooled to 0° C. DIPEA (1.711 ml, 9.80 mmol) was added dropwise followed by 1,1-dimethylethyl hydrazinecarboxylate (0.949 g, 7.18 mmol) and the solution was left to stir at 20° C., under an argon atmosphere for 18 hours. A dark brown solution formed and LCMS showed the desired compound to be present. The solvent was removed under reduced pressure and the residue was diluted with dichloromethane and washed with saturated sodium bicarbonate, saturated ammonium chloride, water and brine. The organic extracts were dried over magnesium sulfate and the solvent was removed under vacuum to yield the desired product in 1.685 g.

1. waitLCMS after circa 1 hour showed
2. customThe solvent was removed under reduced pressure
3. customthe residue was azeotroped with toluene
4. dissolutionThe residue was dissolved in dichloromethane (DCM) (27.0 ml)
5. temperaturecooled to 0° C
6. waitthe solution was left
7. customA dark brown solution formed

ORD record

ord-a92f0b0c705e481292c83e87a488f44c

Source dataset

uspto-grants-2013_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08501946B2