Completely o -Phenylene Bridged N 4 -Cyclophane: A Missing Link in the Phenylene Bridge N 4 -Cyclophane Family.

Unprecedented types of metal-free complete o -phenylene bridged N 4 -cyclophanes ( M1 and M2 ) have been synthesized via sequential palladium-catalyzed Buchwald-Hartwig N -arylation reactions. These cyclophanes may be considered as aromatic analogues of aliphatic group-spaced N 4 -macrocycles. These have been characterized fully using physicochemical characterization techniques and finally by single crystal X-ray structure determination. Their redox and spectral properties have been characterized by cyclic voltammetry, UV-vis spectro-electrochemistry, fluorescence spectral studies, and DFT calculations. These studies have shown rich redox, spectral, and photophysical properties that could make both M1 and M2 potential candidates for various applications.