Reaction between thiocarbamidoalkyl naphthols and acetylenic esters: An interesting cyclocondensation reaction for the synthesis of new thiazolidin-4-one derivatives

This investigation was set to provide derivatives of thiazolidin-4-ones incorporated with aminoalkyl naphthols in a molecular frame work. For this purpose, a series of 1-thiocarbamidoalkyl-2-naphthols was prepared by the three component condensation of aromatic aldehydes, phenylthiourea and 2-naphthol. In the next step, these compounds underwent reaction with dialkyl acetylenedicarboxylates at ambient temperature in ethanol to afford the corresponding 4-thiazolidinones in high yields. Following the completion of the reaction, the products were solidified and isolated by filtration. The method is easy, inexpensive, chemoselective and environmentally benign and illustrates an interesting instance of click chemistry.