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Two consecutive chemoselective reactions of 1,3-dipolar cycloaddition of terminal alkynes and azides, and amidification of carboxylic acids with primary amines were used to prepare monodisperse sequence-defined oligomers in solution in the absence of protecting groups. Well-defined soluble macromolecular supports such as commercial Wang resin or tailor-made soluble polystyrene allowed the efficient synthesis and cleavage of defined oligomers as well as the preparation of noncleavable block copolymers containing sequence-defined segments.

A new novel and facile pathway for preparing macromolecules by controlling monomer sequence distribution in radical chain polymerizations is explained. The technique can hence be effectively used for synthesizing copolymers with tailor-made microstructures.

The self-organization of random copolymers composed of a nucleobase monomer (either 1-(4-vinylbenzyl)thymine or 9-(4-vinylbenzyl)adenine) and dodecyl methacrylate (DMA) was studied in dilute chloroform solutions. The balance between the molar fractions of the nucleobase monomer (leading to intermolecular H-bonding) and DMA (soluble moiety in chloroform) in the polymer chains was found to be the parameter that principally influences the self-organization. DMA-rich copolymers are molecularly soluble in chloroform, whereas nucleobase-rich copolymers are insoluble in this solvent. Copolymers possessing an equimolar comonomer composition self-assemble into micrometer-sized particles physically cross-linked by intermolecular H-bonds (either thymine-thymine or adenine-adenine interactions, depending on the studied copolymer). Nevertheless, when mixed together, thymine- and adenine-based colloids fuse into thermodynamically stable microspheres cross linked by adenine-thymine interactions.