Hydrochloric Acid → Sodium Chloride

Temperature

10 °C

To a 250 mL three-neck round bottom flask equipped with a reflux condenser was introduced 3-hydrazinopyridine.dihydrochloride (15.0 g, 82.4 mmol). Sodium ethoxide (21 wt % in ethanol, 92.3 mL, 247 mmol) was added over 5 minutes and the pot temperature increased from 23° C. to 38° C. The resultant light brown-slurry was stirred for 10 minutes. Methyl methacrylate (17.7 mL, 165 mmol) was added slowly over 15 minutes and the pot temperature remained at 38° C. The yellow mixture was stirred at 50° C. under nitrogen for 4 hours. The mixture was then cooled down to 10° C. and hydrochloric acid (4 M in 1,4-dioxane, 20.6 mL) was added slowly to quench excess base leading to a light brown suspension. The mixture was concentrated under reduced pressure to afford the title compound as a brown solid as a mixture with sodium chloride (35.2 g, 241%): EIMS m/z 177 ([M]+). The crude material was used directly in the next step.

1. customTo a 250 mL three-neck round bottom flask equipped with a reflux condenser
2. temperaturethe pot temperature increased from 23° C. to 38° C
3. customremained at 38° C
4. stirringThe yellow mixture was stirred at 50° C. under nitrogen for 4 hours
5. customto quench excess base
6. concentrationThe mixture was concentrated under reduced pressure

ORD record

ord-cae85b785fea456ca89cd60fcc3ed6ac

Source dataset

uspto-grants-2015_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09156813B1