反应详情

A solution of 1-(7-bromo-4H-thieno[3,2-c]chromen-2-yl)ethanone (1b) (14 g, 45.3 mmol) in 300 ml of anhydrous dioxane was degassed by passing nitrogen gas for 45 min. Tributyl(1-ethoxyvinyl)stannane (16.35 g, 45.3 mmol) was added to it followed by Pd(PPh3)4 (4.19 g, 3.62 mmol) and PdCl2(dppf)-CH2Cl2 adduct (2.65 g, 3.62 mmol) and the solution was heated at 90 OC for overnight. After cooling, the volume of dioxane was reduced, and a saturated solution of KF was added to it and stirred for 15 min., after which the mixture was passed through a pad of celite and washed with ethyl acetate. The combined filtrate was stirred with 4N HCl solution for 1 h and the organic layer was dried over Na2SO4, filtered and concentrated. The residue was purified by column chromatography to obtain the diacetyl compound (1c) (11.5 g, 68%). m/z 272.9 (M+H)+.

1. customfor 45 min
2. temperaturethe solution was heated at 90 OC for overnight
3. temperatureAfter cooling
4. washwashed with ethyl acetate
5. stirringThe combined filtrate was stirred with 4N HCl solution for 1 h
6. dry with materialthe organic layer was dried over Na2SO4
7. filtrationfiltered
8. concentrationconcentrated
9. customThe residue was purified by column chromatography