Premium
Efficient Palladium‐Catalyzed Aerobic Oxidative Carbocyclization to Seven‐Membered Heterocycles
Author(s) -
Liu Jie,
Bäckvall JanE.
Publication year - 2020
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.202004265
Subject(s) - palladium , catalysis , chemistry , hydroquinone , oxygen , photochemistry , catalytic cycle , oxidative phosphorylation , molecular oxygen , functional group , combinatorial chemistry , organic chemistry , biochemistry , polymer
Abstract The use of molecular oxygen in palladium‐catalyzed oxidation reactions is highly widespread in organic chemistry. However, the direct reoxidation of palladium by O 2 is often kinetically unfavored, thus leading the deactivation of the palladium catalyst during the catalytic cycle. In the present work, we report a highly selective palladium‐catalyzed carbocyclization of bisallenes to seven‐membered heterocycles under atmospheric pressure of O 2 . The use of a homogenous hybrid catalyst (Co(salophen)‐HQ, HQ=hydroquinone) significantly promotes efficient electron transfer between the palladium catalyst and O 2 through a low‐energy pathway. This aerobic oxidative transformation shows broad substrate scope and functional group compatibility and allowed the preparation of O ‐containing seven‐membered rings in good yields in most cases.