Thionyl Chloride → (3,4-dihydro-6-methoxy-2,5,7,8-tetramethyl-2H-benzopyran-2-yl)acetyl chloride

Participants

Reaction Steps

To a solution composed of 3.34 g of (3,4-dihydro-6-methoxy-2,5,7,8-tetramethyl-2H-benzopyran-2-yl)acetic acid, 2 drops of N,N-dimethylformamide and 50 ml of benzene was added 0.87 ml of thionyl chloride, and the mixture was refluxed for 2 hours. After cooling, the reaction mixture was evaporated under reduced pressure to remove the low-boiling substances. The above procedure gave (3,4-dihydro-6-methoxy-2,5,7,8-tetramethyl-2H-benzopyran-2-yl)acetyl chloride in a quantitative yield of 3.56 g.

Provenance & Evidence