Ethyl Nosyloxycarbamate: A Chameleonic Aminating Agent

The purpose of this review is to illustrate the use of ethyl nosyloxycarbamate (NsONHCO2Et). This is a versatile aminating agent known for over 47 years and used to generate, in the presence of organic or inorganic bases under homogeneous conditions, a carbonyl nitrene, a reactive intermediate able to form new C-N or X-N bonds by electrophilic amination reaction of a remarkable variety of nucleophilic substrates. Interest in this reagent has been renewed most recently, during the past dozen years. Operating still in alkaline medium, but under generally heterogeneous conditions, has made possible new synthetic applications for the conjugate base of the same nosyloxycarbamate. These, developed mainly by our research group, allow to carry out direct syntheses of various nitrogenated compounds under mild conditions. The applications span from simple molecules to highly functionalized compounds and many new exciting regio- and stereoselective routes can be envisioned. In particular, it was possible to obtain aziridines containing a cornucopia of assorted functions and therefore able to provide access to more complex molecules under simple operational conditions by using an aminating agent cheap and easy to obtain.