反应详情

To a solution of 4-(4′-chloro-4-ethylbiphenyl-3-yl)-2,2,6,6-tetramethylpyran-3,5-dione (0.141 g, 0.366 mmol) in dry chloroform (3 ml) is added triethylamine (0.152 ml, 1.09 mmol), and methyl chloroformate (0.084 ml, 1.09 mmol) and the mixture is stirred at room temperature for 2 hours. Solvents are removed, and the residue is purified directly by column chromatography (hexane/ethyl acetate 5:1 ratio) to afford carbonic acid 4-(4′-chloro-4-ethylbiphenyl-3-yl)-2,2,6,6-tetramethyl-5-oxo-5,6-dihydro-2H-pyran-3-yl ester methyl ester (0.150 g) as a white solid.

1. customSolvents are removed
2. customthe residue is purified directly by column chromatography (hexane/ethyl acetate 5:1 ratio)