One-pot solvent-free three-component reaction between primary amines, carbon disulfide, and 5-alkylidene rhodanines: a convenient synthesis of asymmetric birhodanines.

One-pot solvent-free three-component reaction between primary amines, carbon disulfide, and 5-alkylidene rhodanines in the presence of a catalytic amount of tetra n-butylammonium bromide proceed at room temperature and produced asymmetric birhodanines in good to high yields within 5 min.