title: Arene-metal π-complexation as a traceless reactivity enhancer for C-H arylation.
abstract: Current approaches to facilitate C-H arylation of arenes involve the use of either strongly electron-withdrawing substituents or directing groups. Both approaches require structural modification of the arene, limiting their generality. We present a new approach where C-H arylation is made possible without altering the connectivity of the arene via π-complexation of a Cr(CO)3 unit, greatly enhancing the reactivity of the aromatic C-H bonds. We apply this approach to monofluorobenzenes, highly unreactive arenes, which upon complexation become nearly as reactive as pentafluorobenzene itself in their couplings with iodoarenes. DFT calculations indicate that C-H activation via a concerted metalation-deprotonation transition state is facilitated by the predisposition of C-H bonds in (Ar-H)Cr(CO)3 to bend out of the aromatic plane.
authors: School of Biological and Chemical Sciences, Queen Mary University of London , Joseph Priestley Building, Mile End Road, E1 4NS London, U.K.
authors: Paolo
authors: P
authors: Ricci
authors: Katrina
authors: K
authors: Krämer
authors: Xacobe C
authors: XC
authors: Cambeiro
authors: Igor
authors: I
authors: Larrosa
mesh_terms: D001555:Benzene Derivatives / Q000737:chemistry*; D002857:Chromium / Q000737:chemistry*; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D011789:Quantum Theory
chemical_list: D001555:Benzene Derivatives; D009942:Organometallic Compounds; D002857:Chromium