反应详情

Benzo[b]thiophen-4-ol (200, 4.3 g, 28.9 mmol) and iso-butanol (3.2 ml, 34.7 mmol) are dissolved under argon in 150 ml of toluene. After addition of triphenylphosphine (9.1 g, 34.7 mmol) and a 40% solution of DEAD in toluene (16.8 ml, 34.7 mmol), the mixture is stirred at 120° C. over night. After cooling down, the reaction mixture is subsequently washed with saturated aqueous NaHCO3 solution and NaCl solution, dried over Na2SO4 and evaporated under reduced pressure. Triphenylphosphinoxid is removed by crystallization from ethyl acetate and hexane and the crude product is further purified by flash chromatography (silica gel, hexane/ethyl acetate 9:1).

1. temperatureAfter cooling down
2. washthe reaction mixture is subsequently washed with saturated aqueous NaHCO3 solution and NaCl solution
3. dry with materialdried over Na2SO4
4. customevaporated under reduced pressure
5. customTriphenylphosphinoxid is removed by crystallization from ethyl acetate and hexane
6. customthe crude product is further purified by flash chromatography (silica gel, hexane/ethyl acetate 9:1)