Synthesis of a cyclic diaryl ether derivative under solid-phase conditions

The TTN phenolic oxidation, along with the N-protective group of the corresponding tripeptide derivatives, was examined to accomplish construction of a cyclic isodityrosine derivative under solid-phase conditions. The desired cyclization was effected under the TTN (thallium(III) trinitrate)/NMP–MeOH conditions to give the corresponding 17-membered ring lactam 12.