反应详情

Butyllithium solution, 2.5m in hexanes (1.70 mL, 4.24 mmol) was added dropwise to a solution of 2-bromo-3-(ethoxymethoxy)pyridine (0.98 g, 4.24 mmol) in THF 25 mL at −78° C. The reaction was stirred for 25 min. Then N-(7-bromo-3-chloro-5H-chromeno[2,3-c]pyridin-5-ylidene)-2-methylpropane-2-sulfinamide (1.35 g, 3.26 mmol, prepared as in Example 18b) in THF was added. The reaction was warmed up to RT and stirred for 1 h. The reaction was quenched with aq. ammonium chloride and extracted with EtOAc. The organic phase was separated and washed with brine, dried over sodium sulfate, filtered and concentrated. The crude material was purified by column chromatography with 25-60% EtOAc/Hexane to give 0.94 g of desired product. The resulting material was dissolved in dry MeOH 10 mL and cooled in an ice bath. Hydrochloric acid, 4.0M solution in 1,4-dioxane (20 mL, 80 mmol) was added and mixture was stirred at RT for 4 h. The reaction was quenched with 10% sodium carbonate solution and extracted with DCM three times. The combined organic layers were washed with brine, dried on sodium sulfate, filtered and concentrated to give the desired product which was used without further purification.

1. stirringstirred for 1 h
2. customThe reaction was quenched with aq. ammonium chloride
3. extractionextracted with EtOAc
4. customThe organic phase was separated
5. washwashed with brine
6. dry with materialdried over sodium sulfate
7. filtrationfiltered
8. concentrationconcentrated
9. customThe crude material was purified by column chromatography with 25-60% EtOAc/Hexane