Generation and capture of iminyl radicals from ketoxime xanthates

Irradiation of ketoxime O-(S-methyl xanthates) containing a gamma,delta-dou ble bound leads to a dihydropyrrole through cyclisation of an intermediate iminyl radical in a radical chain reaction. The last propagation step invol ves transfer of a dithiocarbonate group and various external radical traps can be incorporated into the medium, allowing access to a variety of substi tuted dihydropyrroles.