Synthesis of soluble conjugated polymeric nanoparticles through heterogeneous Suzuki coupling reaction

- Suzuki polycondensation of multi-functional monomers (Ax + By, x > 2, y ≥ 2) were studied.
- Soluble conjugated polymeric nanoparticles were produced in heterogeneous systems.
- The growth of the nanoparticles was regulated by the decomposition of boronic acid.
- The size of the nanoparticles was controllable by variation of the reaction condition.

Conjugated hyperbranched polyphenylene nanoparticles are fabricated by cross coupling reactions between an A2 type monomer 1,4-phenylenediboronic acid (1) and B3 type monomers 1,3,5-triiodobenzene (2) and 1,3,5-tribromobenzene (3). The Suzuki-type polycondensation was conducted with a highly efficient heterogeneous catalyst to give conjugated polymeric nanoparticles which are soluble in a variety of organic solvents. The growth of the hyperbranched polyphenylenes are controlled and eventually terminated by the decomposition of the boronate terminal groups in basic aqueous media in the heterogeneous catalysis system. This method represents a new approach to produce soluble conjugated polymeric nanoparticles with simple and symmetrical monomers with more than two end groups (Ax + By, x ≥ 2, y > 2).