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Oxidative Coupling of Anionic Abnormal N‐Heterocyclic Carbenes: Efficient Access to Janus‐Type 4,4′‐Bis(2 H ‐imidazol‐2‐ylidene)s
Author(s) -
Grineva Alina A.,
Valyaev Dmitry A.,
César Vincent,
Filippov Oleg A.,
Khrustalev Victor N.,
Nefedov Sergei E.,
Lugan Noël
Publication year - 2018
Publication title -
angewandte chemie international edition
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.831
H-Index - 550
eISSN - 1521-3773
pISSN - 1433-7851
DOI - 10.1002/anie.201801530
Subject(s) - carbene , chemistry , steric effects , intramolecular force , adduct , pincer movement , medicinal chemistry , imes , aryl , oxidative coupling of methane , janus , stereochemistry , derivative (finance) , photochemistry , organic chemistry , catalysis , nanotechnology , materials science , alkyl , economics , financial economics
The oxidative coupling of anionic imidazol‐4‐ylidenes protected at the C2 position with [MnCp(CO) 2 ] or BH 3 led to the corresponding 4,4′‐bis(2 H ‐imidazol‐2‐ylidene) complexes or adducts, in which the two carbene moieties are connected through a single C−C bond. Subsequent acidic treatment of the later species led to the corresponding 4,4′‐bis(imidazolium) salts in good yields. The overall procedure offers practical access to a novel class of Janus‐type bis(NHC)s. Strikingly, the coplanarity of the two NHC rings within the mesityl derivative 4,4′‐bis(IMes), favored by steric hindrance along with stabilizing intramolecular C−H⋅⋅⋅π aryl interactions, allows the alignment of the π‐systems and, as a direct consequence, significant electron communication through the bis(carbene) scaffold.