2-Pyridinecarboxamide, 4-acetyl- (9CI) synthesis

Yield:135450-71-4 90%

Reaction Conditions:

with dipotassium peroxodisulfate;oxygen;sodium formate;silver nitrate in water at 80; for 4 h;Schlenk technique;regioselective reaction;

Steps:

general procedure for Ag-catalyzed carbamoylation

General procedure: A 25 mL Schlenk flask was charged with AgNO₃ (17.2 mg, 20 mol% Ag), K₂S₂O₈(408 mg, 1.5 mmol), and HCOONa (129 mg, 1.0 mmol) before standard cycles of evacuation and back-filling with dry and pure oxygen (three times). Corresponding pyridine 1 (0.5 mmol), formamide 2 (2 mL), and H₂O (0.4 mL) were added successively. The mixture was stirred at 80 °C for the indicated time (monitored byTLC). At the end of the reaction, the reaction mixture was cooled to room temperature, poured into a saturated aqueous NaCl solution (15 mL), and extracted with ethyl acetate (3 × 15 mL). The organic phases were combined, and the volatile components were evaporated in a rotary evaporator. The residue was purified by flash column chromatography on silica gel to afford the corresponding product 3

References:

Han, Wei;Jin, Fengli;Zhao, Qian;Du, Hongyan;Yao, Lifang [Synlett,2016,vol. 27,# 12,art. no. ST-2016-W0059-L,p. 1854 - 1859] Location in patent:supporting information