tert-Butyl Nitrite Mediated Regiospecific Nitration of (E)-Azoarenes through Palladium-Catalyzed Directed CH Activation

An efficient protocol for the Pd-catalyzed regiospecific ortho-nitration of (E)-azoarenes has been achieved for the first time using tBuONO as a nitrating agent under atmospheric oxygen. A series of both symmetrical and unsymmetrical azoarenes were nitrated efficiently by this procedure providing excellent chemo- and regioselectivity and compatibility with a broad array of functional groups.