Item


Aryl-copper(III)-acetylides as key intermediates in Csp2-C sp model couplings under mild conditions

The mechanism of copper-mediated Sonogashira couplings (so-called Stephens-Castro and Miura couplings) is not well understood and lacks clear comprehension. In this work, the reactivity of a well-defined aryl-Cu III species (1 ClO 4) with p-R-phenylacetylenes (R=NO2, CF3, H) is reported and it is found that facile reductive elimination from a putative aryl-CuIII-acetylide species occurs at room temperature to afford the Caryl - Csp coupling species (IR), which in turn undergo an intramolecular reorganisation to afford final heterocyclic products containing 2H-isoindole (PNO2, PCF3, PHa) or 1,2-dihydroisoquinoline (PHb) substructures. Density Functional Theory (DFT) studies support the postulated reductive elimination pathway that leads to the formation of C sp2-Csp bonds and provide the clue to understand the divergent intramolecular reorganisation when p-H-phenylacetylene is used. Mechanistic insights and the very mild experimental conditions to effect C aryl-Csp coupling in these model systems provide important insights for developing milder copper-catalysed Caryl - C sp coupling reactions with standard substrates in the future

We acknowledge financial support from European Research Council for Starting Grant Project ERC-2011-StG-277801 to X. R., MICINN of Spain (INNPLANTA project INP-2011-0059-PCT-420000-ACT1 to X. R., CTQ2012-32436 to T. P., CTQ2012-37420-C02-01/BQU to Dr. M. Costas, RyC contract to J.Ll.-F. and PhD FPI grant to M. F.), Consolider-Ingenio CSD2010-00065, and the Catalan DIUE of the Generalitat de Catalunya (2009SGR637). X. R. thanks an ICREA-Academia award

Wiley-VCH Verlag

Manager: European Research Council
Ministerio de Ciencia e Innovación (Espanya)
Author: Rovira Coll, Mireia
Font Molins, Marc
Acuña-Parés, Ferran
Parella Coll, Teodor
Luis Luis, Josep Maria
Lloret Fillol, Julio
Ribas Salamaña, Xavi
Abstract: The mechanism of copper-mediated Sonogashira couplings (so-called Stephens-Castro and Miura couplings) is not well understood and lacks clear comprehension. In this work, the reactivity of a well-defined aryl-Cu III species (1 ClO 4) with p-R-phenylacetylenes (R=NO2, CF3, H) is reported and it is found that facile reductive elimination from a putative aryl-CuIII-acetylide species occurs at room temperature to afford the Caryl - Csp coupling species (IR), which in turn undergo an intramolecular reorganisation to afford final heterocyclic products containing 2H-isoindole (PNO2, PCF3, PHa) or 1,2-dihydroisoquinoline (PHb) substructures. Density Functional Theory (DFT) studies support the postulated reductive elimination pathway that leads to the formation of C sp2-Csp bonds and provide the clue to understand the divergent intramolecular reorganisation when p-H-phenylacetylene is used. Mechanistic insights and the very mild experimental conditions to effect C aryl-Csp coupling in these model systems provide important insights for developing milder copper-catalysed Caryl - C sp coupling reactions with standard substrates in the future
We acknowledge financial support from European Research Council for Starting Grant Project ERC-2011-StG-277801 to X. R., MICINN of Spain (INNPLANTA project INP-2011-0059-PCT-420000-ACT1 to X. R., CTQ2012-32436 to T. P., CTQ2012-37420-C02-01/BQU to Dr. M. Costas, RyC contract to J.Ll.-F. and PhD FPI grant to M. F.), Consolider-Ingenio CSD2010-00065, and the Catalan DIUE of the Generalitat de Catalunya (2009SGR637). X. R. thanks an ICREA-Academia award
Document access: http://hdl.handle.net/2072/295560
Language: eng
Publisher: Wiley-VCH Verlag
Rights: Tots els drets reservats
Subject: Compostos organometàl·lics
Organometallic compounds
Coure
Copper
Funcional de densitat, Teoria del
Density functionals
Mecanismes de reacció (Química)
Reaction mechanisms (Chemistry)
Title: Aryl-copper(III)-acetylides as key intermediates in Csp2-C sp model couplings under mild conditions
Type: info:eu-repo/semantics/article
Repository: Recercat

Subjects

Authors


Warning: Unknown: write failed: No space left on device (28) in Unknown on line 0

Warning: Unknown: Failed to write session data (files). Please verify that the current setting of session.save_path is correct (/var/lib/php5) in Unknown on line 0