3,4-Alkylenedioxypyrroles:  Functionalized Derivatives as Monomers for New Electron-Rich Conducting and Electroactive Polymers

Abstract

New functionalized derivatives of 3,4-ethylenedioxypyrrole (EDOP, 5a) and 3,4-(1,3-propylenedioxy)pyrrole (ProDOP, 5b) as especially electron-rich monomers which yield highly electroactive and stable conducting polymers useful for a diverse set of applications have been synthesized. N-Alkylations of ProDOP were carried out to yield a variety of ProDOP derivatives having alkyl, sulfonatoalkoxy, glyme, and glyme alcohol pendant chains. Iodization of EDOP and ProDOP via iodo-decarboxylation afforded iodo-functionalized derivatives useful for subsequent aryl coupling chemistry. N-Protection and formylation of EDOP, followed by Knoevenagel condensation of the resultant 2-formyl-EDOP with aryl acetonitrile derivatives, led to 1-cyano-2-(2-(3,4-ethylenedioxypyrryl))-1-(2-thienyl)vinylene (23) (Th-CNV-EDOP) and 1-cyano-2-(2-(3,4-ethylenedioxypyrryl))-1-(2-(3,4-ethylenedioxythienyl)vinylene (26) (EDOT-CNV-EDOP). A 14-crown-4-ether 34 based dioxypyrrole was synthesized with a cavity potentially useful for lithium ion coordination and sensing in the resultant electroactive polymer. C-Alkylated ProDOPs (43a, 43b, and 43c) containing octyl, ethylhexyl, and dioctyl substituents appended to the central methylene of the propylene bridge, were prepared as monomers for potentially soluble π-conjugated polymers