Acetyl chloride → HCID 21829927, compound

Participants

Reaction Conditions

Reaction Steps

6.4 g (20 mmol) of 6-tert-butyl-5-chloro-4-hydroxy-3-(2,4,6-trimethylphenyl)-2-pyrone (Ex. I-a-4) are initially charged in 50 ml of ethyl acetate. At 20° C., 2.02 g (20 mmol) of triethylamine are added, and at 0° C. a solution of 1.6 g (20 mmol) of acetyl chloride in 20 ml of ethyl acetate is added dropwise. The mixture is subsequently stirred at 20° C. for 20 h. Precipitated triethylamine hydrochloride is filtered off with suction and washed with ethyl acetate. The combined mother liquors are washed twice with 50 ml of half-concentrated sodium chloride solution each time, dried over magnesium sulphate and concentrated under reduced pressure. 7.2 g of crude product are obtained. Flash chromatography over silica gel 60 (35-70 μm) using toluene:acetone 30:1 as eluent yields 4.1 g (57% of theory) of 4-acetyloxy-6-tert-butyl-5-chloro-(2,4,6-trimethylphenyl)-2-pyrone of melting point 116-118° C.

Provenance & Evidence