An achiral anthracene−pyrimidine derivative (5-(9-anthracenyl)pyrimidine, 1) forms adduct 1·Cd(NO3)2·H2O·EtOH (2) in chiral space group P21. The metal ion is hexacoordinated with two pyrimidine ligands (equatorial cis), water and ethanol (equatorial cis), and two nitrate ions (axial trans). The chirality arises from a pyrimidine−Cd2+ helical array and is preserved not only in each crystal via homochiral interstrand water−nitrate hydrogen bonding but also in all the crystals in the same chirality as a result of single-colony homochiral crystal growth. Compound 1 also forms achiral (Pbca) trihydrate adduct 1·Cd(NO3)2·3H2O (3) having nonhelical pyrimidine−Cd2+ zigzag chains. Achiral zigzag polymer 3 and chiral helical polymer 2 are interconvertible with each other in the solid states upon exchange of volatile ligands (ethanol and water). The helix winding associated with the conversion of adduct 3 to 2 can be made homochiral by seeding.

Anthracene−monoresorcinol derivative 1 forms hydrogen-bonded poly(resorcinol) 1D chains, which self-assemble via interpenetration or intercalation of the orthogonal anthracene (A) substituents. Guest-binding in the resulting cavities leads to either, depending on the guests (G, aromatic or aliphatic), an alternate ···A·G·A·G··· (monomeric) or an ···A·A·G·G··· (dimeric) lattice pattern. The monomeric lattices show a remarkable linear-alkyl vs branched-alkyl selectivity in the guest-binding. The dimeric lattices are characterized by their exclusive emission of excimer fluorescence. Self-assembly of the present 1D chains is thus functional and also flexible and dynamic; removal, addition, and exchange of guest molecules readily occur in the solid states.

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