Multicomponent Coupling Approach to Cross-Conjugated Polymers from Vanillin-Based Monomers

We describe the use of vanillin-based monomers as a renewable feedstock for the synthesis of cross-conjugated polymers. This transformation exploits a catechyl-substituted phosphonite mediated multicomponent polymerization to convert vanillin-derived diimines, commercial diacid chlorides, and simple alkynes or alkenes into conjugated pyrrole-based polymers. The flexibility of the multicomponent polymerization has allowed for the efficient formation of families of vanillin-derived fluorescent polymers with tunable properties. This includes coupling vanillin with furan-based acid chlorides as the first cross-conjugated polymer composed of both components of lignocellulosic biomass.