Mesitylene → Edaglitazone

Participants

Reaction Conditions

Reaction Steps

A 100 ml, 4-necked glass flask equipped with a mechanical stirrer, a thermometer, a cooler, a dropping funnel and an argon inlet was charged under argon in sequence with 9.20 g (19.6 mmol) of 5-[[4-[2-(5-methyl-2-phenyl-4-oxazolyl)ethoxy]benzo[b]thien-7-yl]methylene]-2,4-thiazolidinedione, 7.84 g (29.4 mmol) of 3,5-pyridinedicarboxylic acid, 1,4-dihydro-2,6-dimethyl-, diethyl ester and 43 ml of mesitylene. The suspension was stirred at reflux (ca. 167° C.) for 6 h, then the heating bath was removed. When the resulting suspension had a temperature of ca. 85° C. 125 ml of ethanol were added. After 2 h stirring at room temperature the precipitate was isolated by filtration, the filter cake was washed with 50 ml of ethanol and dried at 56° C./1 mbar for 2 h to afford 8.46 g (92%) of 5-{[4-[2-(5-methyl-2-phenyl-oxazol-4-yl)ethoxy]benzo[b]thiophen-7-yl]methyl}-2,4-thiazolidinedione as off-white crystalline material, which according to HPLC analysis had 99.3% purity.

Provenance & Evidence