反应详情

A mixture of 0.3 g of rac-3,4-dihydro-2,5,7,8-tetramethyl-2-(phenylethynyl)-2H-1-benzopyran-6-ol, 7 ml of pyridine and 0.5 ml of acetic anhydride was allowed to sit at room temperature over night. The reagents were evaporated under reduced pressure, at the end azeotropically with toluene. The residue was crystallized from hexane to give 0.21 g of colorless crystals with m.p. 123°-125°.

1. waitto sit at room temperature over night
2. customThe reagents were evaporated under reduced pressure, at the end azeotropically with toluene
3. customThe residue was crystallized from hexane