Collect. Czech. Chem. Commun. 1995, 60, 1578-1586

Reaction of Carbon Disulfide with Active Methylenes: Novel Synthesis of Thiophene, Thieno[2,3-b]thiophene, Thieno[3,2-c]pyrazole and Thieno[3,2-b]pyridine Derivatives

Rafat M. Mohareba, Sherif M. Sherifa, Adiba Habashia, Nadia I. Abdel-Sayedb and Samia S. Osmana

a Department of Chemistry, Faculty of Science, University of Cairo, Giza, Egypt
b Department of Chemistry, College for Girls, Ain Shams University, Helioplis, Cairo, Egypt


The active methylene compounds - derivatives of malonic or 4-oxobutanoic acid - reacted with carbon disulfide in dimethyl formamide containing potassium hydroxide to yield the non-isolable dipotassium disulfide intermediates. The latter were cyclized by α-haloketones to give thiophene, thieno[2,3-b]thiophene, thieno[3,2-c]pyrazole and thieno[3,2-b]pyridine derivatives. The reactivity of the products toward various reagents was studied.