Synthesis of 4h-thieno[3,2-c]chromenes by intramolecular arylation of 4-aryloxy-methyl-5-iodothiophene-2-carbaldehydes

摘要

The iodination of 4-chloromethylthiophene-2-carbaldehyde by N-iodosuccinimide under solvent-free conditions gives 4-chloromethyl-5- iodothiophene-2-carbaldehyde, which is used to obtain 4-aryloxy-methyl-5- iodothiophene-2-carbaldehydes. The palladium-catalyzed intramolecular cyclization of 4-aryloxymethyl-5-iodothiophene-2-carbaldehydes yields 4H-thieno[3,2-c]chromene-2-carbaldehydes.