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A dynamic, supramolecular, three-component AnBmCl bis(zinc porphyrin) tweezer has been prepared quantitatively using the heteroleptic bisphenanthroline (HETPHEN) concept. Upon addition of nitrogenous spacers of different length, namely, the extended bipyridine 3 a, 4,4′-bipyridine (3 b), and 1,4-diazabicyclo[2.2.2]octane (DABCO; 3 c), to set up an additional orthogonal binding motif (ZnPor–Nspacer), three structurally different, still dynamic, four-component AnBmClDk assemblies were cleanly formed, as indicated by UV/Vis and NMR titrations as well as by DOSY investigations. The structures were identified as a bridged monotweezer A2BC2D, a doubly bridged double tweezer A4B2C4D2, and a triply bridged double tweezer A4B2C4D3, the latter resembling a porphyrin stack. Notably, the same structures were equally formed directly from a mixture of the constituents A, B, C, and D put together in any sequence if the correct stoichiometry was applied.
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