Phosphorus trichloride → HCID 136340685, compound

Participants

Reaction Steps

To a suspension of crude 2-(5-cyano-2-oxoindolin-3-yl)-8-hydroxy-5,6,7,8-tetrahydroquinoline 1-oxide (263 mg, 0.819 mmol) in ethyl acetate (12 mL) and acetonitrile (12 mL) was added dropwise a solution of phosphorous trichloride (0.644 mL, 7.37 mmol) in ethyl acetate (4 mL). The resulting suspension was stirred at RT. After 24 h the mixture was diluted with ethyl acetate and washed with a saturated sodium bicarbonate solution (2×). The aqueous phase was re-extracted with ethyl acetate (1×) and the combined organic extracts were dried over sodium sulfate, filtered, and evaporated to dryness (52 mg). The crude was dissolved in a mixture of water (2 mL) and dimethylformamide (3 mL) and the solution was heated in a microwave oven at 120° C. for 5 min. After cooling to RT the reaction mixture was diluted with ethyl acetate was washed with brine (5×). The organic layer was dried over sodium sulfate, filtered, and evaporated to dryness. The crude was purified by flash chromatography (silica gel, dichloromethane/methanol) yielding yellow solid. Amount 8.6 mg. Yield 18%.

Provenance & Evidence