Configuration and conformation of poly(3-carbazolylacetylene) including cis and trans radicals revealed by ESR spectroscopy

Abstract

π-Conjugated cis and trans radicals of poly(N-isobutyl-3-carbazolylacetylene) were stereospecifically prepared using the [Rh(norbornadiene)Cl]2-NEt3 catalyst, and their geometric structures were determined using the electron spin resonance (ESR) method.

Ultrastable Supramolecular Self‐Encapsulated Wide‐Bandgap Conjugated Polymers for Large‐Area and Flexible Electroluminescent Devices

“…π‐Stacked aromatic groups based on sp 3 nitrogen are known to show excellent self‐assembling and charge transporting behavior . In this work, we introduced a π‐stacked carbazole (Cz) group into polyfluorene as a pendent steric synthon to fabricate a novel supramolecular bulky wide‐bandgap LCPs, PHDPF‐Cz (Scheme B; Figure S1, Supporting Information) .…”

“…Herein, we originally proposed that a supramolecular self‐encapsulation strategy, which tethered bulky conjugated polymers with the π‐stacked self‐assembled units at side chain, is a versatile molecular design tool to achieve such complementariness ( Scheme A). π‐Stacking of aromatic groups located at the side chain assembles into a sheath that surrounds the chain backbone, in analogy with electric power cords, thus serving as “intermediate centers” to enable interchain charge transport and simultaneously to hinder interchain π–π interaction in solid states (Scheme C) …”

“…π-Stacking of aromatic groups located at the side chain assembles into a sheath that surrounds the chain backbone, in analogy with electric power cords, thus serving as "intermediate centers" to enable interchain charge transport and simultaneously to hinder interchain π-π interaction in solid states (Scheme 1C). [40,41] Inspired by the supramolecular steric hindrance (SSH) effect of bulk units on molecular conformation and packing, we proposed a novel strategy based on the molecular integration of steric bulk groups and supramolecular synthons into one functional molecule or chain (Scheme 1A). [42,43] For all the effort put into the design of polyfluorenes over the last few decades, [12] the utilization of the fluorene 4,5 position has been completely ignored.…”

“…π-Stacked aromatic groups based on sp 3 nitrogen are known to show excellent self-assembling and charge transporting behavior. [40,[47][48][49][50][51] In this work, we introduced a π-stacked carbazole (Cz) group into polyfluorene as a pendent steric synthon to fabricate a novel supramolecular bulky wide-bandgap LCPs, PHDPF-Cz (Scheme 1B; Figure S1, Supporting Information). [12] PHDPF-Cz together with the controlled polymers PHDPF, PODPF, PNDPF, and PFO was synthesized following our previous works (Scheme S1, Supporting Information).…”

Proposed Mechanism for the High-Yield Polymerization of Oxyethyl Propiolates with Rh Complex Catalyst Using the Density Functional Theory Method

“…Moreover, an active monodentate Rh complex catalyst can be generated in situ from a Rh bidentate catalyst when amine, alcohol, or even water is used as the cocatalyst or solvent [13,14,15,16,17,18,19,20,21,22]. The [Rh(nbd)Cl] 2 /amine binary catalyst system has been reported to be a significantly effective catalyst for the polymerization of various phenyl acetylene derivatives and propargyl esters [23,24,25,26,27,28,29,30,31,32,33,34]. Propiolic esters, however, are sluggish when used as a monomer for the Rh catalyst system, due to their strong acidity.…”