Nonlinear Optical Dendrimers from Click Chemistry: Convenient Synthesis, New Function of the Formed Triazole Rings, and Enhanced NLO Effects

The new synthetic approach to develop nonlinear optical (NLO) dendrimers with click chemistry and azo coupling reaction was demonstrated. The finished dendrimers were well characterized and demonstrated excellent dendritic structure, blue-shifted absorption, and enhanced NLO performance. A reactive alkyne group was also introduced for the further growing of the dendrimers. It was observed that as the ratios of the nitro groups to the carbonyl increased along with the growth of the NLO dendrimers from first generation to the third, the absorption intensity of the nitro groups became more stronger. Gel permeation chromatography (GPC) was used for the analysis of the dendrimer growth. It was also observed that sharpless 'click' reaction could be used for the construction of NLO dendrimers with good performance. The click chemistry reaction provided the convenient synthesis of NLO dendrimers.