Contemporary Approaches for Conventional and Light‐Mediated Synthesis of Conjugated Heteroaromatic Polymers

Abstract

𝝅-Conjugated polymers (CPs) are industrially important materials with vast application in the fabrication of many high-tech devices. Particularly, CPs based on heteroaromatic monomers (CHAPs) receive great interest due to their superior optoelectronic properties. CHAPs are generally synthesized by classical cross-coupling or electrochemical polymerizations, but these methods come with major drawbacks. This review summarizes novel approaches for conventional and light-mediated polymerizations, which overcome the shortcomings associated with these traditional approaches. Special emphasis is devoted to the photooxidative polymerization methods developed by the group for the production of CHAPs.

Photoproduction of High Molecular Weight Poly (N-methylpyrrole) under Green Conditions

“…In the context of sustainable chemistry, lightdriven chemical methods are the most favorable techniques due to the faster reaction rates, milder reaction conditions and the use of much less or no solvent (bulk photopolymerization) (26,27). Photopolymerization reactions use only light as the input energy and don't require excess amount of toxic catalysts/solvents (28).…”

Phenacyl Bromide as a Single‐Component Photoinitiator: Photoinduced Step‐Growth Polymerization ofN‐Methylpyrrole andN‐Methylindole

“…[10] Cross-coupling methods which are the mostly applied techniques for COPs, require highly inert atmosphere and refluxing conditions. [11] Classical chemical polymerization methods for COPs involve the excess use of oxidizing metal salts which are hard to remove the trace amount that deteriorates the optoelectronic properties of the final polymer. [12] Electrochemical production of COPs avoids the use of any metal salts.…”

Sonochemistry-assisted photocontrolled atom transfer radical polymerization enabled by manganese carbonyl

“…4–6 RDRPs modulated by external stimuli have received intense attention because they are capable of providing spatiotemporal control over polymerization, decreasing energy demands and avoiding side reactions. 7–18…”

“…[4][5][6] RDRPs modulated by external stimuli have received intense attention because they are capable of providing spatiotemporal control over polymerization, decreasing energy demands and avoiding side reactions. [7][8][9][10][11][12][13][14][15][16][17][18] Photocatalytic approaches have been developed to convert light into chemically reactive species that mediate the controlled synthesis of well-defined polymers. [19][20][21] One possibility for conducting photoinduced polymerizations is via the direct generation of activating radicals by the photoinduced cleavage of compounds, which can also mediate the deactivation and control the polymerization process.…”