Nucleophilic Substitution Polymerization-Induced Emission of 1,3-Dicarbonyl Compounds as a Versatile Approach for Aggregation-Induced Emission Type Non-Traditional Intrinsic Luminescence

Nucleophilic substitution reaction and 1,3-dicarbonyl compounds play significant roles in organic chemistry, and non-traditional intrinsic luminescence (NTIL) has become an emerging research area. Here, we demonstrate the successful nucleophilic substitution polymerization of 1,3-dicarbonyl compounds, including acetylacetone, 3,5-heptanedione, methyl acetoacetate, cyclopentane-1,3-dione, 1,3-indandione, 1-phenyl-1,3-butanedione and dibenzoylmethane, where reactive hydrogens at α position of 1,3-dicarbonyl compounds are involved. Through this base catalyzed nucleophilic substitution polycondensation between 1,3-dicarbonyl compounds and α,α’-dibromo xylene, a series of nonconjugated poly(1,3-dicarbonyl)s have been successfully prepared with high yield (up to >99%) under mild conditions. Investigations reveal that this nucleophilic substitution polycondensation exhibits self-accelerating effect and flexible stoichiometry characteristics, which exhibits advantages over traditional polycondensation methods. This polymerization also exhibits intriguing polymerization-induced emission (PIE) characteristics, where nonconjugated poly(1,3-dicarbonyl)s exhibit intriguing chemical structure dependent aggregation-induced emission (AIE) type NTIL. This work therefore expands the monomer, method, chemical structure and property libraries of polymer chemistry, which may cause inspirations to polymerization methodology, PIE, AIE and NTIL.

Super-Grignard reagents(R_(2)Mg·LiCl)mediated covalent-anionic-radical polymerization capable of low?and reactive hydrogen compatibility

The precise synthesis of polymer with narrow molecular weight distribution(?)and well-defined architectures is very essential to exploring the functions and properties of polymer materials.Here,a universal polymerization method capable of low?and reactive hydrogen compatibility is reported by introducing super-Grignard reagents(R_(2)Mg?Li Cl)into polymer chemistry.Under mild conditions,various monomers,including nonpolar polystyrene and 4-methoxystyrene that cannot be initiated by Grignard reagents,and polar methacrylate,are successfully polymerized with full monomer conversion and low?.This approach is amenable to wide varieties of initiators,polymerization temperature,and feed ratio,which makes it attractive for applications in polymer synthesis.By adding methanol and water during the polymerization process,the reactive hydrogen compatibility of this method is confirmed,which makes this method avoid the rigorous restriction on polymerization conditions of anionic polymerization.Moreover,chain extension polymerization and block copolymerization are achieved and demonstrate the livingness of chain propagation,enabling the facile synthesis of well-defined macromolecular architectures.This work therefore expands the methodology libraries of living polymerization,which may cause inspirations to polymer science.