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Bipyrrole boomerangs via Pd-mediated tandem cyclization-oxygenation. Controlling reaction selectivity and electronic properties.

ABSTRACT: Boomerang-shaped bipyrroles containing donor-acceptor units were obtained through a tandem palladium-mediated reaction consisting of a cyclization step, involving double C-H bond activation, and a double ?-oxygenation. The latter reaction can be partly suppressed for the least reactive systems, providing access to ?-unsubstituted boomerangs for the first time. These "?-free" systems are highly efficient fluorophores, with emission quantum yields exceeding 80% in toluene. Preliminary measurements show that helicene-like boomerangs may be usable as circularly polarized luminescent materials.

SUBMITTER: Moshniaha L

PROVIDER: S-EPMC7214875 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

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Bipyrrole boomerangs via Pd-mediated tandem cyclization-oxygenation. Controlling reaction selectivity and electronic properties.

Moshniaha Liliia L Żyła-Karwowska Marika M Cybińska Joanna J Chmielewski Piotr J PJ Favereau Ludovic L Stępień Marcin M

Beilstein journal of organic chemistry 20200504

Boomerang-shaped bipyrroles containing donor-acceptor units were obtained through a tandem palladium-mediated reaction consisting of a cyclization step, involving double C-H bond activation, and a double α-oxygenation. The latter reaction can be partly suppressed for the least reactive systems, providing access to α-unsubstituted boomerangs for the first time. These "α-free" systems are highly efficient fluorophores, with emission quantum yields exceeding 80% in toluene. Preliminary measurements ...[more]

PMID: 32461771

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