Hydrogen Peroxide → HCID 90010639, compound

Participants

Reaction Conditions

Reaction Steps

Step-2: 5-(3-Ethylpyridin-4-yl)-3-methyl-1,3,4-oxadiazol-2(3H)-one: The title compound was prepared from ethyl-3-ethylisonicotinate by following the similar procedure sequentially as described instep-2, step-3 and step-4 of Intermediate-1a. 1HNMR (400 MHz, CDCl3) δ 8.63 (s, 1H), 8.59 (d, J=5.0 Hz, 1H), 7.64 (d, J=5.0 Hz, 1H), 3.56 (s, 3H), 3.03 (q, J=7.5 Hz, 2H), 1.28 (t, J=7.5 Hz, 3H); GC-MS (m/z) 205 (M)+ Step-3: 3-Ethyl-4-(4-methyl-5-oxo-4,5-dihydro-1,3,4-oxadiazol-2-yl)pyridine-1-oxide: To a stirred solution of step-2 intermediate (3.50 g, 17.1 mmol) in acetic acid (30 mL) was added hydrogen peroxide (0.62 mL, 20.4 mmol) drop-wise at RT and the resulting mixture was heated to 80° C. and maintained for 12 h. The reaction was cooled to RT and basified with solid potassium carbonate. The resulting slurry was diluted with DCM (50 mL) and filtered. The filtrate was concentrated under vacuum to afford 2.70 g (70%) of the title compound as white solid. GC-MS (m/z) 221 (M)+.

Provenance & Evidence