4-Pyridinecarboxamide,3-hydroxy-(9CI) synthesis

Yield:10128-73-1 50%

Reaction Conditions:

with ammonia in methanol at 120; for 5 h;

Steps:

B B. 3-Hydroxyisonicotinamide

B.
3-Hydroxyisonicotinamide
0.072 mol (12 g) 3-hydroxyisonicotinic acid ethyl ester and 0.72 mol ammonia (103 ml 7 M solution in methanol) were heated in a pressure vessel to 120° C. for 5 h.
Then the reaction mixture was evaporated until dryness, suspended with 165 ml tetrahydrofuran and heated under reflux for 30 min.
After cooling the product was filtered off and dried. 5 g (50% yield) of the title compound were obtained. IR (in substance, cm^-1): 1699, 1665, 1638, 1597, 1561, 1498, 1440, 1418, 1349, 1310, 1250, 1227, 1197, 1096, 1063, 1027, 911, 788, 767, 672, 653, 623.
LC-MS (m/z): 139.4 (M+H).
CHN-elementary analysis: C, 50.92; H, 4.21; N, 19.16.
1H-NMR (DMSO-d₆, 400 MHz): δ [ppm]=8.52 (s, 1H), 8.37 (s, 1H), 8.21 (s, 1H), 8.18 (d, 1H), 7.80 (d, 1H).

References:

US2016/15716,2016,A1 Location in patent:Paragraph 0130; 0131; 0132; 0133; 0134