Oxidative ring-opening of aziridine-1-carboxylates with sulphoxides

Abstract

The title reaction furnishes a practical preparation of α-carbalkoxyamino ketones from nitrene adducts of the corresponding olefins. The aziridines are alternatively accessible via addition,of iodine isocyanate, alcoholysis and elimination of hydrogen iodide. DMSO-cleavage of cis and trans isomers of 1-carbethoxy-2-methyl-3-phenylaziridine proceeds regioselectively: the cis isomer reacts at 1,2-bond and 1,3-bond in a ratio of ca 1:1, whereas the trans isomer reacts at 1,3-bond almost exclusively. The 1,3-bond cleavage is predominant under acidic conditions for both isomers. Under neutral conditions, the cleavage proceeds via an SN2 type transition state. © 1970.