Hydrochloric Acid → HCID 178437669, compound

Aqueous glyoxal (50 ml), was added over one minute to a stirred solution of 2-aminobutanamide hydrobromide (61.9 g), in aqueous methanol (650 ml methanol, 70 ml water) at -40° C. 10.8M Aqueous sodium hydroxide solution (76.6 ml) was then added over one hour, keeping the temperature at -40° C. The reaction was then allowed to warm to ambient temperature over 18 hours and concentrated hydrochloric acid (41 ml) was added, followed by solid sodium hydrogen carbonate (33 g). The reaction mixture was filtered and the filtrate concentrated to a volume of approximately 100 ml. The concentrated solution was extracted with dichloromethane (3×250 ml), and the combined organic extracts were dried (MgSO4). Solvent was removed by evaporation to give 3-ethyl-2-hydroxypyrazine as a yellow solid, (30.3 g, 74%); 1H NMR (d6 -DMSO, 200 MHz): 1.15 (t,3H), 2.67 (q,2H), 7.15-7.25 (m,2H), 12.00 (s,1H); mass spectrum (+ve CI): 125 (M+H)+.

1. customat -40° C
2. filtrationThe reaction mixture was filtered
3. concentrationthe filtrate concentrated to a volume of approximately 100 ml
4. extractionThe concentrated solution was extracted with dichloromethane (3×250 ml)
5. dry with materialthe combined organic extracts were dried (MgSO4)
6. customSolvent was removed by evaporation

ORD record

ord-153f24b1ec3946de8f35ac4d555b43ce

Source dataset

uspto-grants-1999_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05861401