Primary sequences encoded into the suite of tricarb macrocycles were shown by scanning-tunneling microscopy (STM) to impact the next levels of supramolecular ordering (4°) and 2D crystalline polymorphs (5°) at solution–graphite interfaces. The resulting macrocycles are planar (2° structure) and form H-bonded dimers (3°) at surfaces. The linear build up of primary sequence (1°) also enabled a thermal Huisgen cycloaddition to proceed regioselectively for the first time using geometric control. We developed a new stepwise synthesis with sequence-defined targets made in 11, 17, and 22 steps with 25, 10, and 5% yields, respectively. To design macrocycles with one (AAA), two (AAB), or three (ABC) different carbazole units, we needed to subvert the synthetic preferences for one-pot macrocyclizations. We do this here by providing the first proofs that sequence controls the hierarchical assembly of nonbiological macrocycles, in this case, at graphite surfaces. This idea has been applied to all manner of oligomers but not to the behavior of cyclic oligomers, aka macrocycles. Anfinsen’s dogma that sequence dictates structure is fundamental to understanding the activity and assembly of proteins.
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