Synthesis Of Conjugated Porous Organic Polymers Using Metathesis

Abstract

Conjugated porous organic polymers (CPOPs) are a class of polymers that have persistent porosity and inherently amorphous. Due to their extended conjugation and porosity these materials can be applied in sensors, light emitting devices, transistors, diodes, capacitors, catalysis, and several other devices. Different reactions have been utilized for synthesizing CPOPs like aryl-aryl cross coupling reactions, cyclotrimerization. More recently, reversible reactions have been used to form covalent organic frameworks (COFs). It is believed that reversible reactions enable error correction over the period of the reaction time. This leads to high surface area materials and also predictable solid-state order. However, most of the reactions utilized in the synthesis of conjugated porous organic polymers are irreversible, thus limiting the highest achievable surface area. The reactions utilized for making CPOPs and COFs are limited. Here I report the development of conjugated polymer networks synthesized by reversible reactions: alkene and alkyne metathesis. Trisphenylene vinylene polymers (TPV) synthesized by alkene metathesis were utilized to detect low volatility explosives like RDX and PETN from vapor phase, for the first time. CPOPs were synthesized using alkyne metathesis catalyst (trisamido)molybdenum alkylidyne, after extensive studies on kinetic activities of the catalyst. Both these studies highlighted the vast scope of the metathesis reactions in the synthesis of CPOPs and the applications like explosive sensing, that result from the extended conjugation in the system, which has a potential application in real world explosive sensors. iii