@article{10272/16190,
year = {2017},
url = {http://hdl.handle.net/10272/16190},
abstract = {The catalytic functionalization of the Csp
2-H bond of benzene by means of the insertion of the CHCO2Et
group from ethyl diazoacetate (N2=CHCO2Et) has been studied with the series of coinage metal complexes IPrMCl (IPr =
IPr = 1,3-bis(diisopropylphenyl)imidazol-2-ylidene) and NaBArF
4 (BArF
4 = tetrakis(3,5-bis(trifluoromethyl)phenyl)borate).
For Cu and Ag, these examples constitute the first of such metals toward this transformation, that also provides ethyl
cyclohepta-2,4,6-trienecarboxylate as by-product from the so-called Buchner reaction. In the case of methyl-substituted
benzenes, the reaction exclusively proceeds onto the aromatic ring, the Csp
3-H bond remaining unreacted. A significant
coinage metal effect has been observed, since the gold catalyst favors the formation of the insertion product into Csp
2-H
bond whereas copper and silver preferentially induce the formation of the cycloheptatriene derivative. Experimental studies
and theoretical calculations have explained the observed selectivity in terms of the formation of a common Wheland
intermediate, resembling an electrophilic aromatic substitution, from which the reaction pathway evolves into two separate
routes to each product.},
organization = {We thank the Spanish MINECO for CTQ2014-52769-C3-1-R, CTQ2014-57761-R, RED INTECAT CTQ2014-52974-REDC and Severo Ochoa Excellence Accreditation 2014-2018 SEV-2013-0319 and the ICIQ Foundation for financial support.},
publisher = {American Chemical Society},
keywords = {Copper},
keywords = {Silver and gold catalysis},
keywords = {Arene C-H bond functionalization},
keywords = {Carbene transfer},
keywords = {Diazo reagents},
title = {Mechanistic Studies on Gold-Catalyzed Direct Arene C–H Bond Functionalization by Carbene Insertion: The Coinage-Metal Effect},
doi = {10.1021/acs.organomet.6b00604},
author = {Romero Fructos-Vázquez, Manuel and Besora, María and Braga, Ataualpa A. C. and Díaz Requejo, María Mar and Maseras, Feliu and Pérez Romero, Pedro José},
}