Helix Sense-Selective Supramolecular Polymerization Seeded by a One-Handed Helical Polymeric Assembly

Helix sense-selective supramolecular polymerization was achieved using a one-handed helical nanotubular polymeric assembly as a seed. First, bipyridine (BPY)-appended achiral hexabenzocoronene (^BPYHBC) was copolymerized noncovalently with chiral ^BPYHBC_S (or ^BPYHBC_R) at a molar ratio of 9:1, which, via the sergeants-and-soldiers effect, afforded a P-helical (or M-helical) nanotube, which was then treated with Cu²⁺ to transform into structurally robust ^(BPY)CuNT_(P) (or ^(BPY)CuNT_(M)) with a Cu²⁺/BPY coordination polymer shell. Helical seeds ^(BPY)CuNT_(P) and ^(BPY)CuNT_(M) brought about the controlled assembly of fluorinated chiral FHBC_S and FHBC_R as well as achiral FHBC to yield one-handed helical nanotubular supramolecular block copolymers, in which the helical senses of the newly formed block segments were solely determined by those of the helical seeds employed. Noteworthy, FHBC_S and FHBC_R alone without the helical seeds form ill-defined agglomerates. Attempted supramolecular polymerization of a racemic mixture of FHBC_S and FHBC_R from ^(BPY)CuNT_(P) (or ^(BPY)CuNT_(M)) resulted in its chiral separation, affording P-helical (or M-helical) diastereomeric block segments composed of FHBC_S and FHBC_R with different thermodynamic properties.