1,4-Phenylene-linked cyclotrimer () and cyclotetramer () have been synthesized via Lewis acid-catalyzed self-condensation of appropriate precursors. Structural and Density Functional Theory (DFT) studies reveal the disruption of annulenic conjugation in both and by linking phenylene rings prevented them from global antiaromaticity. The single crystal X-ray structure of reveals all the nitrogens are pointing toward the macrocyclic core with near-planar and square-shaped geometry, thus in sharp contrast to the ring-strained conformation of .

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http://dx.doi.org/10.1021/acs.orglett.1c03903DOI Listing

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