Dimethylformamide → (S)-7-bromo-3-(neopentyloxy)-5'H-spiro[chromeno[2,3-b]pyridine-5,4'-oxazol]-2'-amine

Participants

Reaction Conditions

Reaction Steps

To a solution of (S)-2′-amino-7-bromo-5′H-spiro[chromeno[2,3-b]pyridine-5,4′-oxazol]-3-ol (390 mg, 1.120 mmol) in DMF (4481 μL, 1.120 mmol) in a sealed tube was added cesium carbonate (912 mg, 2.80 mmol). After stirring for 1 minute neopentyl iodide (223 μL, 1.680 mmol) was added, the reaction vessel was sealed and heated at 100° C. for 2.5 hours. Reaction was cooled to RT to prevent over alkylation. The reaction was diluted with water (25 mL) and 10 mL of ethyl acetate and stirred for 30 minutes before being poured into a separatory funnel containing ethyl acetate (100 mL) and water (250 mL). The layers were separated and the aqueous layer was extracted with ethyl acetate (3×50 mL). The aqueous layer was then extracted with DCM (3×50 mL). The organic layers were each washed with water and then brine, at which point all the organics were combined, dried over sodium sulfate, filtered and concentrated in vacuo to provide a brown foam that was purified by silica gel chromatography (Redi-Sep pre-packed silica gel column (40 g), 0-10% methanol in methylenechloride with 0.1% ammonium hydroxide) to provide (S)-7-bromo-3-(neopentyloxy)-5′H-spiro[chromeno[2,3-b]pyridine-5,4′-oxazol]-2′-amine as a yellow solid.

Provenance & Evidence