Ultrasound assisted remote functionalization of non-activated carbon atoms: efficient in situ formation of tetrahydrofurans by sonolysis of bromohydrins with (diacetoxyiodo)benzene/I2

Abstract

Ultrasonic irradiation of bromohydrins in the presence of (diacetoxyiodo)benzene and I2 generates alkoxyl radicals which lead in situ to intramolecular hydrogen abstraction on the C-19 non-activated carbon atoms in steroids producing tetrahydrofurans selectively in very good yields. Photolysis was less effective in promoting such conversions.