Fig. 1. (a) Templated synthesis of a duplex forming molecule through reductive amination. The template sequence organizes the monomers (or codons) favouring the formation of the complementary sequence imine oligomer, which can be finally reduced to the more stable amine. (b) Structure comparison of duplex forming oligoanilines. There are three key design elements that can be independently optimised in a highly modular approach: the coupling chemistry used for the synthesis of oligomers (green), the recognition module responsible for intermolecular binding (blue/red) and the backbone which links these components together (black). The long-short 2-trifluoromethylphenol–phosphine oxide base-pairing system is shown, along with a backbone that is assembled through reductive amination (R = 2-ethylhexyl). Reported approaches are based on the two components assembly of aldehyde monomers and short (i) or long (ii) aniline linkers. The system described here is based on the assembly of recognition encoded monomers equipped with both aniline and aldehyde moieties (iii). This design allows duplex formation in chloroform without the undesired 1,2-folding and shows template effect.