Copper-Catalyzed Synthesis of Dibenzo[ b , f ]imidazo[1,2- d ][1,4]oxazepine Derivatives via a Double Ullmann Coupling Reaction.

A double Ullmann coupling reaction successfully takes place between 4,5-diaryl-2-(2-bromophenyl)-1 H -imidazoles and 2-bromophenols in the presence of Cs2 CO3. This procedure is catalyzed by copper(I) iodide and o -phenanthroline and provides an efficient method for the synthesis of dibenzo[ b , f ]imidazo[1,2- d ][1,4]oxazepine derivatives in good yields. [ABSTRACT FROM AUTHOR]