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Abstract Poly(thienylene vinylene)s (PTV's) are early examples of conjugated polymers but have not been extensively studied when compared with closely analogous polythiophenes. PTV's synthesized through previously reported techniques are similar in structures that contain various alkyl or alkoxy side‐chains that exert limited impact on the polymer electronic properties. Herein, we report the preparation of a series of regio‐regular PTV's (rr‐PTV's) bearing cross‐conjugated side‐chains through ADMET polymerization of a common brominated di(thienylene vinylene) (DTV) monomer followed by PPM reactions on the resulting brominated PTV. These new polymers contain a bulky silyloxy alkyl side‐chain and a functionalized thiophene moiety on every main‐chain thiophene unit, and their regio‐regular placement is confirmed by NMR spectroscopy. The thienyl based side‐groups broaden polymer absorption ranges and at the same time lead to uncommon emission properties that are results of light‐induced charge transfer events between the polymer main‐chains and side‐chains. Removal of the silyl groups on one of these rr‐PTV's led to insoluble materials and x‐ray diffraction experiments on the collected solids displayed distinct scattering peaks that are absent from similarly functionalized regio‐random PTV's reported previously, thus suggesting better crystallinity originated from regio‐regularity.
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Highly Luminescent Ladderized Fluorene Copolymers Based on B–N Lewis Pair Functionalization
Abstract A new B–N functionalized polyaromatic building block for conjugated hybrid polymers is developed. Bromine‐functionalized dipyridylfluorene is first subjected to Lewis‐base‐directed electrophilic borylation and subsequently incorporated into conjugated polymers via transition‐metal‐catalyzed cross‐coupling reactions. The borane monomer exhibits bright blue luminescence in solution, as a result of the rigid ladder‐type structure generated upon electrophilic borylation. Yamamoto coupling gives rise to a homopolymer and Stille coupling to a vinylene‐bridged copolymer. Polymerization of the BN‐fused ladder molecules leads to large bathochromic shifts in absorption and emission, which are most pronounced for the vinylene‐bridged copolymer. The polymers display strong luminescence in solution with quantum yields of 55% and 78% and sub‐ns fluorescence lifetimes; the copolymer also exhibits bright yellow luminescence in the solid state when precipitated from solution.
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- PAR ID:
- 10067317
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Macromolecular Rapid Communications
- Volume:
- 39
- Issue:
- 22
- ISSN:
- 1022-1336
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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