Synthesis, electrical conductivity and electron paramagnetic resonance spectroscopy of polymers derived from NOPF6-doped XYZ-triheterocycles based on pyrrole, furan and thiophene

Abstract

A series of triheterocycles; [graphic omitted] for X, Y, Z = OOO, SSS, SOS, SSO, OSO, SOO, O(N-Me)O, S(N-Me)O and S(N-Me)S have been synthesised; of these O(N-Me)O, SOO and S(N-Me)O are new. The triheterocycles were chemically polymerised and oxidised with NOPF6. Only the polymers derived from SSS, SOS and SSO show appreciable conductivities. EPR studies indicate the presence of polarons in SSS, SOS, SSO and, at lower concentrations, in OOO. All the samples appear to show an easily saturable EPR signal assigned to localised radicals. In OSO, SOO, O(N-Me)O, S(N-Me)O and S(N-Me)S this signal displays considerable asymmetry, and g-values significantly above the free electron value. S(N-Me)S shows a higher g-value consistent with a loss of planarity.