5-[4-(2,4,5-Trimethyl-3,6-dimethoxyphenoxy)benzyl]thiazolidine-2,4-dione → 5-[4-(3,5,6-Trimethyl-1,4-benzoquinon-2-yloxy)benzyl]thiazolidine-2,4-dione

Participants

Reaction Steps

A solution of 2.1 g of ceric ammonium nitrate in a mixture of 2 ml of water and 2 ml of acetonitrile was added dropwise at 0° C. to a solution of 0.4 g of 5-[4-(2,4,5-trimethyl-3,6-dimethoxyphenoxy)benzyl]thiazolidine-2,4-dione (prepared as described in Preparation 2) in 3 ml of acetonitrile, and the resulting mixture was stirred at the same temperature for 1 hour. At the end of this time, the reaction mixture was poured into water, after which it was extracted with ethyl acetate. The extract was washed with a saturated aqueous solution of sodium chloride and then dried over anhydrous sodium sulfate. The solvent was then removed from the extract by distillation under reduced pressure, and the residue thus obtained was purified by column chromatography through silica gel, using a 4:1 by volume mixture of benzene and ethyl acetate as the eluent, to give 260 mg of the title compound, melting at 153°-156° C. (with decomposition).

Provenance & Evidence