反应详情

Compound 16B (5 g) and concentrated HCl (2 mL) in MeOH (200 mL) were heated to reflux for 30 h. The reaction mixture was quenched with water (200 mL) and ether (200 mL). Separated the organic layer, washed with water, brine, dried (MgSO4), concentrated to give an off-white solid, compound 16C (4.2 g). mp 56-57° C.; MS: 191 (M+1)+. Preparation of 6-Chlorosulfonyl-2H-chromene-3-carboxylic acid methyl ester (Compound 16D)

1. temperatureto reflux for 30 h
2. customThe reaction mixture was quenched with water (200 mL) and ether (200 mL)
3. customSeparated the organic layer
4. washwashed with water, brine
5. dry with materialdried (MgSO4)
6. concentrationconcentrated