Structure of the IN3 Adduct of 1-Phenylcyclohexene. Its Chemistry and CH Coupling as a Diagnostic Tool¹

The addition of iodine azide to alkenes, discovered by Hassner et al.,² is by now a well-established method for stereo- and regiospecific introduction of nitrogen functional groups.² In a recent paper, Sivasubramanian et al.³ claimed that the regiochemistry of the IN₃ addition to 1-aryl-l-cyclohexenes was the reverse of that usually observed for conjugated aromatic alkenes. Thus, the IN₃ adduct of 1-phenylcyclohexene, originally assigned structure 1 by Hassner et al.,⁴was claimed to be instead the tertiary iodide 2.³ The unsaturated azide obtained on dehydroio-dination of the adduct with hot KOH in ethanol was assigned structure 3.³.