The use of carbon disulfide provides a novel and efficient route for the synthesis of thiopyrans. Herein we describe a study on the pseudo-five-component preparation of 4 H- thiopyran derivatives by condensation of aldehydes, malononitrile, carbon disulfide, and primary amines in the presence of triethylamine. Separation and identification of the reaction intermediates and products, additional starting materials designing, repeating of the reaction, and determining of the products, NMR, and GC-mass analysis of the reaction mixtures, were used to evaluate and confirm the reaction pathway.
