反应详情

A dichloromethane solution of 5-(2-hydroxyethyl)-7-methoxy-2-benzofuran-1(3H)-one was placed cooled to 0° C., and slowly treated with methanesulfonyl chloride (0.11 mL, 1.4 mmol) and TEA (0.2 mL, 1.44 mmol). The resulting mixture was then stirred for 20 min. TLC (hexanes/EtOAc=1/1) indicated completion of the reaction. The mixture was poured into saturated ammonium chloride and extracted with dichloromethane. The combined organics were washed with 1 N HCl, saturated sodium bicarbonate solution, and brine, then dried (Na2SO4) and concentrated in vacuo. To the residue (LC/MS: [(M+1)]+=287; tR=0.81 min) (0.16 g, 0.56 mmol) was added DBU (0.19 mL, 1.26 mmol) and dichloromethane (2 mL) and stirred for 2 h. TLC monitoring showed conversion to the olefin. The reaction mixture was diluted with water and extracted with dichloromethane. The combined organics were washed with 1N HCl, saturated sodium bicarbonate solution, and brine, then dried (Na2SO4) and concentrated to dryness. The resulting oil was used in the next step without further purification.

1. customcompletion of the reaction
2. extractionextracted with dichloromethane
3. washThe combined organics were washed with 1 N HCl, saturated sodium bicarbonate solution, and brine
4. dry with materialdried (Na2SO4)
5. concentrationconcentrated in vacuo
6. stirringstirred for 2 h
7. extractionextracted with dichloromethane
8. washThe combined organics were washed with 1N HCl, saturated sodium bicarbonate solution, and brine
9. dry with materialdried (Na2SO4)
10. concentrationconcentrated to dryness
11. customThe resulting oil was used in the next step without further purification