Cyclopropanation of Aryl and Styryl Acetonitriles With Selenium-Based Dielectrophiles

Base-promoted cyclopropanations of aryl or styrylacetonitriles with vinyl selenones are described. The formation of the two new C−C bonds proceeds through a Michael addition followed by a cyclization. Such reactions are usually difficult with pronucleophiles not bearing an additional geminal electron-withdrawing group. Operational simplicity, transition metal-free mild conditions, high yields and excellent regio- and diastereocontrol are advantages of this protocol.