2-Methyl-3-cyanoimidazo(1,2-a)pyridine synthesis

Yield:19768-70-8 80%

Reaction Conditions:

with pyridine;trifluoroacetic anhydride in tetrahydrofuran at 20;Cooling with ice;

Steps:

40-B.iii

001151] (iii) Production of 2-methylimidazo[l,2-a]pyridine-3-carbonitrile[001152] To a mixture of 2-methylimidazo[l,2-a]pyridine-3-carboxamide (3.50 g, 20 mmol) produced above, pyridine (4.85 mL, 60 mmol) and tetrahydrofuran (50 mL) was added dropwise a solution of trifluoroacetic anhydride (4.24 mL, 30 mmol) in tetrahydrofuran (10 mL) under ice-cooling. The mixture was stirred at room temperature for 1 hr, saturated aqueous sodium bicarbonate solution was added, and the mixture was extracted with ethyl acetate. The collected organic layer was washed with saturated brine and dried over anhydrous magnesium sulfate, and the insoluble material was filtered off. The filtrate was concentrated under reduced pressure, and the obtained residue was washed with ethyl acetate/diisopropyl ether to give the title compound (2.5 g, 80%) as a pale-brown solid.[001153] ¹H-NfMR (DMSOd₆, 300 MHz) δ 2.49 (3H, s), 7.19 (IH, dt, J = 1.1, 6.8 Hz), 7.56 (IH, ddd,J = 1.2, 7.0, 9.0 Hz), 7.73 (IH, td, J = 1.1, 9.0 Hz), 8.59 (IH, td, J = 1.1, 6.8 Hz).

References:

WO2010/90716,2010,A1 Location in patent:Page/Page column 322