反应详情

A suspension of 2-aminothiophene-3-carboxamide (6.26 g, 44.0 mmol), potassium carbonate (6.08 g, 44.0 mmol), 2-dicyclohexylphosphino-2′,4′,6′-triisopropyl-1,1-biphenyl (0.667 g, 1.40 mmol), dibenyzlideneacetone bis(triphenylphosphine) (0.293 g, 0.32 mmol), and 2-bromo-6-methylpyridine (4.55 mL, 40 mmol) in tert-amyl alcohol (80 mL) in a 250 mL round bottom flask with attached reflux condenser was placed under an argon atmosphere by performing six vacuum/argon flush cycles. The reaction was heated to reflux for 18 hours. The flask was charged with more 2-dicylohexylphosphino-2′,4′,6′-triisopropyl-1,1-biphenyl (0.330 g, 0.7 mmol) and dibenyzlideneacetone bis(triphenylphosphine) (0.146 g, 0.160 mmol) and refluxed for an additional 24 hours. The reaction mixture was diluted with ethyl acetate (200 mL) and saturated aqueous sodium bicarbonate, and this suspension was filtered. The layers of the filtrate were separated and the organic layer was washed with brine (100 mL), dried over sodium sulfate, filtered, and concentrated. The resulting solid was triturated with a 1:1 mixture of ethyl acetate and hexanes to afford the title compound as a grey solid.

1. temperaturewith attached reflux condenser
2. customflush cycles
3. temperatureThe reaction was heated
4. temperatureto reflux for 18 hours
5. temperaturerefluxed for an additional 24 hours
6. filtrationthis suspension was filtered
7. customThe layers of the filtrate were separated
8. washthe organic layer was washed with brine (100 mL)
9. dry with materialdried over sodium sulfate
10. filtrationfiltered
11. concentrationconcentrated
12. customThe resulting solid was triturated with a 1:1 mixture of ethyl acetate and hexanes