(3+2)-Cycloaddition Of Donor-Acceptor Cyclopropanes With Selenocyanate: Synthesis Of Dihydroselenophenes And Selenophenes

We present a Lewis-acid-catalyzed (3 + 2)-cycloaddition of donor-acceptor cyclopropanes and selenocyanate (as its tetramethylammonium salt) for the synthesis of dihydroselenophenes. The transformation proceeded with moderate to excellent yields and showed a high functional group tolerance. Further oxidation using DDQ delivered selenophenes.