Yield:875293-89-3 54.1%

Reaction Conditions:

with trichlorophosphate at 0 - 90; for 2 h;

Steps:

36.c

5-Methyl-1-oxy-pyridine-2-carbonitrile (2.6 g, 19 mmol) was added in batches to phosphorus oxychloride (CAN 10025-87-3, 20 mL) at 0° C. The reaction mixture was heated to 90° C. for 2 h. The volatiles were then removed and the remaining residue was neutralized with a saturated solution of sodium bicarbonate. This mixture was extracted with ethyl acetate (3×30 mL) and the combined extracts were dried over anhydrous sodium sulfate and evaporated. The residue was purified by column chromatography (silica gel, 30 g, 10% ethyl acetate in petroleum ether) to yield the title compound (1.6 g, 10 mmol, 54.1%) as yellow solid; MS (EI): m/e=153.1 [M+H]⁺.

References:

US2012/316147,2012,A1 Location in patent:Page/Page column 45