Regioselectivity of the (ethoxycarbonyl)nitrene insertion reaction on monochloro- and dichloroalkanes and cycloalkanes

Ethyl azidoformate has been thermolyzed in 1,1-dichloropentane, 1,1-dichlorohexane, 1,1-dichlorocyclohexane, 7,7-dichlorobicyclo[4.1.0]heptane, 1-chlorohexane, 1-chlorooctane, and chlorocyclohexane. All substrates showed a distribution of the insertion products quite different from the statistical one. The general trend was the preferential introduction of the functional group far from the chlorine atom(s). Inversely, chlorocyclohexane gave a large amount (33.5%) of trans-1-chloro-2-[(ethoxycarbonyl)amino]cyclohexane. The results are discussed in terms of probable coordination of the nitrene by heteroatom lone-pair electrons, in addition to polar and steric effects. © 1979 American Chemical Society.