Copper(I)-catalyzed azide-alkyne cycloaddition-assisted polymerization of linear glucose-derived co/polymers

The synthesis of linear and controllable oligomers and polymers using sugar-derived monomers is still highly challenging. Herein, we present a method allowing the linear polymerization of a bifunctional glucose derivative as monomer, which contained an azide group at C1 and a propargyl group at C4 position of the glucose ring. The reaction conditions were optimized by grafting the monomer onto the surface of silica nanoparticles (SiNPs) and at the end-modified polyethylene glycol (PEG). For grafting the surface of SiNPs with the monomer, an azide-bearing chlorosilane linker was synthesized and introduced onto SiNPs surface. The copper(I)-catalyzed azide-alkyne cycloaddition using the glucose-derived monomer led to the growth of linear triazole-linked oligosaccharide-mimics on the surface of SiNPs with a degree of polymerization up to 13 and the formation of cyclic trimers and tetramers in the solution. Furthermore, during polymerization of the monomer at end-modified PEG, various linear diblock-copolymers pseudo-cellulose-block-PEG and triblock-copolymers pseudo-cellulose-block-PEG-block-pseudo-cellulose were obtained. The polymerization reactions expired with nearly complete consumption of the monomer and high yields between 88 and 94% were achieved. Obtained block-copolymers showed amphiphilic properties that helped to fractionate obtained polymers into lower and higher molecular weight fractions with narrow polymer dispersity D.