Synthesis of Homogeneous Polymer-based Photoredox Catalysts
Restricted (Penn State Only)
Author:
Griggs, Anna
Area of Honors:
Chemistry
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
Elizabeth A Elacqua, Thesis Supervisor Benjamin James Lear, Thesis Honors Advisor Katherine Mary Masters, Faculty Reader
Keywords:
photoredox catalysis polymer
Abstract:
Continuing advances in catalyst design enable challenging transformations under mild conditions. Photoredox catalysis is an emerging area wherein radicals can be generated under mild conditions using visible light. Single-chain polymer nanoparticles (SCNPs) with pendant organic photoredox active groups have been studied for their impact on organic reactions, such as [2+2] cycloadditions and oxidations reactions. The SCNPs, which contain organic photocatalysts (e.g., triphenylpyrylium), are formed through the crosslinking of pendant styrylarenes and are homogenous catalysts that contain confined spaces. Herein, the synthesized SCNP is used in a [2+2+2] cyclization of aryl alkynes and nitriles and the subsequent reactivities are compared to that of a similar small molecule photoredox complex. While organic catalysts are beneficial for their minimization of toxic waste, metal-based photoredox catalysts are often more potent in organic reactions and could potentially be recovered and recycled. The synthesis and characterization of metal-based polymer-bound catalysts, and their use as catalysts in organic reactions are also reported herein. These results will be compared to the results of similar experiments performed with similar small-molecule catalysts or entirely organic polymers.