Christopher F. Beaulieu, Rodney D. Brown, et al.
Magnetic Resonance in Medicine
Paper
Functionalized azo dyes by direct Ullmann coupling
Abstract
A variety of thermally stable 4-(N,N-diarylamino)-4′-nitroazobenzene dyes can be produced by direct copper-mediated C-N bond formation on preformed amino substituted azo dyes, thus avoiding a troublesome azo coupling step; the products are useful chromophores for high temperature nonlinear optical applications.