Synthesis of tetrasubstituted thiophenes starting from amino mercaptoacrylates and a-brominated acetamides

: Some thiophenic derivatives show important biological activity or are used as intermediates in organic synthesis. For this reason, it is very important to develop new synthesis procedures with good yields and using few synthesis steps. The present work offers an over-view of the method for obtaining substituted thiophenes reported in the literature, and the synthetic procedures used from push-pull systems. In this work, we present the synthesis of 14 new tetrasubstituted thiophenes starting from amino mercaptoacrylates and a-brominated acetamides, derived from furoyl and benzoylacetonitrile, respectively. Best yields (66 to 85%) were obtained through ultrasonic irradiation. Combined use of spectroscopic methods and elementary analysis was used for characterization of all the compounds.