Sequence‐Independent Synthesis of π‐conjugated Arylenevinylene Oligomers using Bifunctional Thiophene Monomers

Abstract

Sequence‐independent or “click” chemistry is applied for the preparation of a series of novel and structurally similar π‐conjugated oligomers. The new oligomers are prepared using Wittig–Horner chemistry from bifunctional building blocks that can be interconnected to one another at any desired sequence. The bifunctional building blocks consist of aromatic skeletons with acetal protected aldehyde groups on one side and a phosphonic acid diethyl ester group para to the aldehyde functionality. The first step in the arylenevinylene formation is a Wittig–Horner coupling of a functionalized aldehyde with the methyl phosphonate ester ylide of a bifunctional monomer. A stepwise protection–deprotection process is applied for the preparation of structurally similar π‐conjugated oligo‐phenylene vinylenes. New di‐, tri‐, penta‐, and hepta‐phenylenevinylenes are prepared and characterized. Selected penta‐arylenevinylenes are incorporated as the semiconductor channel in organic field‐effect transistors.

The Relation Between Molecular Packing or Morphology and Chemical Structure or Processing Conditions: the Effect on Electronic Properties

“…We have reported on the solution synthesis of oligo homo‐ and hetero‐π‐conjugated peptides and their optical and electrical properties . Here, we had applied the LEGO‐like sequence independent and bio‐inspired “click” procedure of double‐bond formation to produce structurally controlled functional oligomers . Using this protocol we were able to prepare two closely related molecules in which two 2,3‐dihydrothieno[3,4‐b][1,4]dioxine (EDOT) units of one oligomer, P1 , are substituted by two 3,3‐dibutyl‐2,4‐dihydrothieno[3,4‐b][1,4]dioxepine groups in the second oligomer, P2 , Figure .…”

“…Materials : All the reagents and solvents described in the manuscript were of analytical grade, purchased from Sigma‐Aldrich and used as received unless noted. The synthesis and characterization of P1 and P2 is described elsewhere …”

Role of the Bridge in Photoinduced Electron Transfer in Porphyrin–Fullerene Dyads

“…The synthetic procedure used for dyad 2 is depicted in Scheme . The first step was the covalent linkage between 2‐(3,4‐ethylenedioxythienyl)carboxaldehyde11 and porphyrin‐based phosphonate 3 12 by Wadsworth–Emmons olefination with t BuOK as a base. The resulting porphyrin derivative 4 , which incorporates the EDOTV unit, was purified by column chromatography (silica gel, hexane/chloroform) and was obtained in 79 % yield.…”

Facile preparation and fluorescence properties of a soluble oligopyrrole derivative

“…Based on those attractive features, conjugated oligomers are regarded as one of promising materials for fabricating electronic and optoelectronic devices [3,4].…”