Abstract
Ketene N,S-acetal potassium salts, prepared via reaction of active methylenes with phenyl isothiocyanate in the presence of potassium hydroxide, were allowed to react with ethylchloroacetate or chloroacetamide to afford the corresponding 2-ylidene-4-thiazolidinones in good yields. These compounds reacted with a variety of aromatic aldehydes to afford the corresponding 5-arylidene-2-ylidene-4-thiazolidinone derivatives.