Premium
Electron‐Deficient Bipyrrole Boomerangs: Bright Fluorophores Obtained via Double C−H Bond Activation
Author(s) -
ŻyłaKarwowska Marika,
Moshniaha Liliia,
Hong Yongseok,
Zhylitskaya Halina,
Cybińska Joanna,
Chmielewski Piotr J.,
Lis Tadeusz,
Kim Dongho,
Stępień Marcin
Publication year - 2018
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.201801199
Subject(s) - photochemistry , intramolecular force , chromophore , femtosecond , conjugated system , chemistry , excited state , electron transfer , double bond , tandem , fluorescence , photoinduced electron transfer , electron transport chain , stereochemistry , materials science , polymer chemistry , laser , atomic physics , organic chemistry , polymer , physics , quantum mechanics , optics , composite material , biochemistry
Pd II ‐mediated annulative double C−H activation is shown to efficiently convert 1, n ‐dipyrrolylalkanes into extensively π‐conjugated bipyrroles not accessible by conventional oxidative coupling protocols. This approach is applicable to both electron‐rich and electron‐deficient systems, and has been further developed into tandem processes involving further cyclization of substituents or oxygenation of pyrrolic α‐positions. The new bipyrrole intermediates show enhanced fluorescence as well as tunable optical properties controlled by the alignment of chromophore subunits. Photophysical data, including femtosecond transient absorptions, reveal solvent‐induced intramolecular charge transfer in their excited states, dependent on the polarity of the medium.