Abstract: The addition reaction of 4-oxo-pente-2-nal or its acetal, which was obtained by hydrolysis of 2-methyl-2,5-dimethoxy-2,5-dihydrofuran, with thioacetic acid and the subsequent cyclization of the 2-thioacetyl or 3-thioacetyl pentenal under different conditions gave β-thioacetyl-furan, β-thioacetylthiophene and β-thioacetylpyrrole derivatives. α-Methyl-β-mercaptofurans, α-methyl-β-mcrcaptothiophenes andα-methyl-β-mercaptopyrroles could be prepared by this method.

Key words: β-Mercaptofurans derivatives, β-Mercaptothiophenes derivatives, β-Mcrcaptopyrroles derivatives, Radical addition, Nucleophilic addition