反应详情

A mixture of 6-hydroxy-(2H)-benzofuran-3-one (5.0 g, 33.3 mmol), methyl (triphenylphosphoranylidene)acetate (25.0 g, 73 mmol), and xylenes (100 mL) is refluxed 6 hr. The reaction is concentrated and diluted with enough 1M aqueous hydrochloric acid to adjust pH to 2-3. The product is extracted into ethyl acetate (3×100 mL). The combined extracts are dried over anhydrous magnesium sulfate, filtered and concentrated. The residue is purified via silica chromatography eluting with 7:3 hexanes:ethyl acetate to afford the product as a orange oil, 1.3 g, 20%. MS M++1 207. The structure is confirmed by 1H NMR spectroscopy.

1. temperatureis refluxed 6 hr
2. concentrationThe reaction is concentrated
3. additiondiluted with enough 1M aqueous hydrochloric acid
4. extractionThe product is extracted into ethyl acetate (3×100 mL)
5. dry with materialThe combined extracts are dried over anhydrous magnesium sulfate
6. filtrationfiltered
7. concentrationconcentrated
8. customThe residue is purified via silica chromatography
9. washeluting with 7:3 hexanes