Selenium heterocycles XXVI. Synthesis of theino[3,4-b]benzofuran and selenolo[3,4-b] benzofuran. Two novel heterocycles

Starting from the readily available aryl 3-methyl-2-benzob] furyl ketones a series of 3-sub-stituted thieno3,4-b] benzofurans and 3-substituted selenolo3,4-b] benzofurans were prepared in high yield. The parent compound, thieno3,4-b] benzofuran was prepared through the reaction of thioacetamide with 2-chloromethyl-3-formylbenzob] furan in moderate yield.