Premium
Highly Luminescent Ladderized Fluorene Copolymers Based on B–N Lewis Pair Functionalization
Author(s) -
Alahmadi Abdullah F.,
Lalancette Roger A.,
Jäkle Frieder
Publication year - 2018
Publication title -
macromolecular rapid communications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.348
H-Index - 154
eISSN - 1521-3927
pISSN - 1022-1336
DOI - 10.1002/marc.201800456
Subject(s) - copolymer , bathochromic shift , luminescence , polymer chemistry , materials science , photochemistry , stille reaction , borylation , fluorene , polymer , chemistry , fluorescence , organic chemistry , aryl , physics , alkyl , optoelectronics , quantum mechanics , composite material
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.