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Juan A: Casares

Juan A: Casares

 

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Juan A. Casares was born in 1961 in León (Spain) and studied chemistry at the Universidad de Valladolid. He obtained his Ph.D. in 1992 under the supervision of Prof. Pablo Espinet, and in 1995 moved to ISSECC (CNR) in Florence, Italy, for a postdoctoral stay. In 1996 he joined the Faculty of Science of the University of Valladolid, where he is Professor since 1997. His research studies include dynamic NMR spectroscopy of square-planar complexes and about catalysis of hydrogenation, silylformylation of alkynes, polymerization, and cross-coupling reactions. Currently his focus is based on the study of reaction mechanisms of palladium-catalyzed cross-coupling and the development of new catalytic multimetallic systems.

Research topics:

Study of reaction mechanisms of reactions catalyzed by transition metals, in particular palladium catalyzed cross-coupling reaction.

Development of new catalytic multimetallic systems.

 

Contact:

casares@qi.uva.es.   Tlfno:+34    983 184 623  or  983 185 808
Área de Química Inorgánica
Facultad de Ciencias, Universidad de Valladolid
Paseo de Belén nº 7 47011 Valladolid
Spain

Recent papers:

Juan del Pozo, Gorka Salas, Rosana Álvarez, Juan A. Casares, Pablo Espinet
“The Negishi Catalysis: Full Study of the Complications in the Transmetalation Step and Consequences for the Coupling Products”
Organometallics, Article ASAP DOI: 10.1021/acs.organomet.6b00660

Desirée Carrasco, Maximiliano García-Melchor, Juan A Casares, Pablo Espinet
“Dramatic Mechanistic Switch in Sn/AuI Group Exchanges: Transmetalation vs. Oxidative Addition”
Chem. Commun., 2016, 52, 4305-4308.
DOI: 10.1039/C5CC10496C

Juan delPozo, Juan A. Casares,Pablo Espinet
“In Situ Generation of ArCu from CuF2 Makes Coupling of Bulky Aryl Silanes Feasible and Highly Efficient”
Chemistry: A European Journal, 2016, Accepted Manuscript.
DOI: 10.1002/chem.201504435
delPozo, J; Gioria, E.; Casares, J. A.; Álvarez, R.; Espinet P.
“Organometallic Nucleophiles and Pd: What Makes ZnMe2 Different? Is Au Like Zn?”
Organometallics, 2015, 34, 3120–3128.
DOI: 10.1021/acs.organomet.5b00329

Ana C. Albeniz, Juan A. Casares
“Palladium-Mediated Organofluorine Chemistry” (Review)
Adv. Organomet. Chem. 201462, 1–110.

M. Calvillo-Barahona, J. A. Casares, C. Cordovilla, M. N. Genov, J. M. Martínez-Ilarduya, P. Espinet
“Diamine-Catalyzed Addition of ZnEt2 to PhC(O)CF3: Two Mechanisms and Autocatalytic Asymmetric Enhancement”
Chem. Eur. J. 2014 DOI: 10.1002/chem.201403648

D. Carrasco, M. H. Pérez-Temprano, J. A. Casares, P. Espinet.
“Cross Alkyl–Aryl versus Homo Aryl–Aryl Coupling in Palladium-Catalyzed Coupling of Alkyl–Gold(I) and Aryl–Halide”
Organometallics2014, Article ASAP. DOI: 10.1021/om500446x

J. delPozo, J. A. Casares, P. Espinet
“Decisive role of Ligand Metathesis in Au/Pd Bimetallic Catalysis”
Chem. Commun. 2013, DOI: 10.1039/C3CC43133A

J. delPozo, D. Carrasco, M. H. Pérez-Temprano, M. García-Melchor, R. Álvarez,  J. A. Casares, P. Espinet
“Stille Coupling Involving Bulky Groups Feasible with Gold Cocatalyst”
Angew. Chem. Int. Ed. 2013, 52, 2189–2193. DOI:  10.1002/anie.201209262

Pérez-Temprano, M. H.; Casares, J. A.; de Lera, A. R.; Álvarez, R.; Espinet, P.
“Strong Metallophilic Interactions in the Palladium Arylation by Gold Aryls”
Angew. Chem. Int. Ed.  201220, 4917–4920

Pérez-Temprano, M. H.; Casares, J. A.; Espinet, P.
“Bimetallic Catalysis using Transition and Group 11 Metals: An Emerging Tool for CC Coupling and Other Reactions”
Chem. Eur. J. 201218, 1864 – 1884.

Garcia-Melchor, M.; Fuentes B., Lledós, A.; Casares, J. A.; Ujaque, G.; Espinet, P.
“Cationic Intermediates in the Pd-Catalyzed Negishi Coupling. Kinetic and Density Functional Theory Study of Alternative Transmetalation Pathways in the Me-Me Coupling of ZnMe2 and trans-[PdMeCl(PMePh2)2]“.
J. Am. Chem. Soc2011, 133, 13519–13526.

Pérez-Temprano, M. H.; Gallego, A. M.; Casares, J. A.; Espinet, P.
“Stille Coupling of Alkynyl Stannane and Aryl Iodide, a Many-Pathways Reaction: The Importance of Isomerization.”
Organometallics201130, 611-617.

Fuentes B.; Garcia-Melchor, M.; Lledós, A.; Maseras, F.; Casares, J. A.; Ujaque, G.; Espinet. P.
“Palladium Round Trip in the Negishi Coupling of trans- [PdMeCl(PMePh2)2] with ZnMeCl. An Experimental and DFT Study of the Transmetallation Step.”
Chem. Eur. J., 201016, 8596-8599.

Salas, G.; Casares, J. A.; Espinet, P.
“Enthalpy of Ligand Substitution in cis Organopalladium Complexes with Monodentate Ligands.”
Dalton Trans2009, 39, 8413-8420.

Carrera, N.; Pérez-Temprano, M.H.; Albéniz, A. C.; Casares, J. A.; Espinet, P.
”A Convenient Quick Synthesis of SnBu2RCl Derivatives.”
Organometallics2009, 28, 3957-3958.

Martín Pérez-Rodríguez, Ataualpa A. C. Braga, Max Garcia-Melchor, Mónica H. Pérez-Temprano, Juan A. Casares, Gregori Ujaque, Angel R. de Lera, Rosana Álvarez, Feliu Maseras, Pablo Espinet.
“The C-C Reductive Elimination in Palladium Complexes, and the Role of Coupling Additives. A DFT Study Supported by Experiment.”
J. Am. Chem. Soc2009131, 3650-3657

Mónica H. Pérez-Temprano, Ainara Nova, Juan A. Casares, Pablo Espinet.
“Observation of a hidden intermediate in the Stille reaction. Study of the reversal of the transmetalation step.”
J Am. Chem. Soc. 2008130,32, 10518-10519.

es

Juan A: Casares

Juan A: Casares

 

my_orcid_qrcode

Juan A. Casares nació en 1961 en León (España). Estudió Química en Valladolid y obuvo su doctorado en 1992 en el Colegio Universitario de Burgos (Universidad de Valladolid) con una Tesis sobre estudios dinámicos en disolución mediante RMN dirigida por el Prof. Espinet. Tras una estancia postoctoral en Florencia (ISSECC)  durante 1995, se incorporó a la Facultad de Ciencias de la Universidad de Valladolid, donde en la actualidad es Profesor.

Ha participado en proyectos de investigación internacionales (3), nacionales (9), y regionales (7), habiendo sido IP de 4 proyectos regionales. En la actualidad es co-Investigador Principal del Proyecto Nacional CTQ2013-48406-P  “Estrategias para una catálisis mas eficaz y limpia: reactivos soportados en polímeros, sistemas multimetálicos, y nuevos ligandos”.

Ha sido conferenciante invitado en distintas reuniones científicas, tanto nacionales (Congreso del GEQO, Huelva, 2010) como internacionales (Gordon Research Conference, Newport, 2014; Reunión ECIRM en Debrecen, Hungría 2014).

Desde 2008 hasta octubre de 2014 ha sido Presidente de la Sección Territorial de Valladolid y Palencia de la Real Sociedad Española de Química.

Líneas de investigación:

Estudio de mecanismos de reacción de reacciones catalizadas por metales de transición, en particular reacciones de acoplamiento cruzado catalizadas por paladio.

Desarrollo de nuevos sistemas catalíticos multimetálicos.

 

Contacto:

casares@qi.uva.es.   Tlfno:+34    983 184 623  or  983 185 808
Área de Química Inorgánica
Facultad de Ciencias, Universidad de Valladolid
Paseo de Belén nº 7 47011 Valladolid
Spain

Publicaciones recientes:

Juan del Pozo, Gorka Salas, Rosana Álvarez, Juan A. Casares, Pablo Espinet
“The Negishi Catalysis: Full Study of the Complications in the Transmetalation Step and Consequences for the Coupling Products”
Organometallics, Article ASAP DOI: 10.1021/acs.organomet.6b00660

Desirée Carrasco, Maximiliano García-Melchor, Juan A Casares, Pablo Espinet
“Dramatic Mechanistic Switch in Sn/AuI Group Exchanges: Transmetalation vs. Oxidative Addition”
Chem. Commun., 2016, 52, 4305-4308.DOI: 10.1039/C5CC10496C

Juan delPozo, Juan A. Casares, Pablo Espinet
“In Situ Generation of ArCu from CuF2 Makes Coupling of Bulky Aryl Silanes Feasible and Highly Efficient”
Chemistry: A European Journal, 2016, 22,4274–4284.
DOI: 10.1002/chem.201504435

Desirée Carrasco, Maximiliano García-Melchor, Juan A Casares, Pablo Espinet
“Dramatic Mechanistic Switch in Sn/AuI Group Exchanges: Transmetalation vs. Oxidative Addition”
Chem. Commun., 2016
DOI: 10.1039/C5CC10496C

delPozo, J; Gioria, E.; Casares, J. A.; Álvarez, R.; Espinet P.
“Organometallic Nucleophiles and Pd: What Makes ZnMe2 Different? Is Au Like Zn?”
Organometallics, 2015, 34, 3120–3128.
DOI: 10.1021/acs.organomet.5b00329

Ana C. Albeniz, Juan A. Casares
“Palladium-Mediated Organofluorine Chemistry” (Review)
Adv. Organomet. Chem. 201462, 1–110.

M. Calvillo-Barahona, J. A. Casares, C. Cordovilla, M. N. Genov, J. M. Martínez-Ilarduya, P. Espinet
“Diamine-Catalyzed Addition of ZnEt2 to PhC(O)CF3: Two Mechanisms and Autocatalytic Asymmetric Enhancement”
Chem. Eur. J. 2014 DOI: 10.1002/chem.201403648

D. Carrasco, M. H. Pérez-Temprano, J. A. Casares, P. Espinet.
“Cross Alkyl–Aryl versus Homo Aryl–Aryl Coupling in Palladium-Catalyzed Coupling of Alkyl–Gold(I) and Aryl–Halide”
Organometallics2014, Article ASAP. DOI: 10.1021/om500446x

J. delPozo, J. A. Casares, P. Espinet
“Decisive role of Ligand Metathesis in Au/Pd Bimetallic Catalysis”
Chem. Commun. 2013, DOI: 10.1039/C3CC43133A

J. delPozo, D. Carrasco, M. H. Pérez-Temprano, M. García-Melchor, R. Álvarez,  J. A. Casares, P. Espinet
“Stille Coupling Involving Bulky Groups Feasible with Gold Cocatalyst”
Angew. Chem. Int. Ed. 2013, 52, 2189–2193. DOI:  10.1002/anie.201209262

Pérez-Temprano, M. H.; Casares, J. A.; de Lera, A. R.; Álvarez, R.; Espinet, P.
“Strong Metallophilic Interactions in the Palladium Arylation by Gold Aryls”
Angew. Chem. Int. Ed.  201220, 4917–4920

Pérez-Temprano, M. H.; Casares, J. A.; Espinet, P.
“Bimetallic Catalysis using Transition and Group 11 Metals: An Emerging Tool for CC Coupling and Other Reactions”
Chem. Eur. J. 201218, 1864 – 1884.

Garcia-Melchor, M.; Fuentes B., Lledós, A.; Casares, J. A.; Ujaque, G.; Espinet, P.
“Cationic Intermediates in the Pd-Catalyzed Negishi Coupling. Kinetic and Density Functional Theory Study of Alternative Transmetalation Pathways in the Me-Me Coupling of ZnMe2 and trans-[PdMeCl(PMePh2)2]“.
J. Am. Chem. Soc2011, 133, 13519–13526.

Pérez-Temprano, M. H.; Gallego, A. M.; Casares, J. A.; Espinet, P.
“Stille Coupling of Alkynyl Stannane and Aryl Iodide, a Many-Pathways Reaction: The Importance of Isomerization.”
Organometallics201130, 611-617.  DOI: 10.1021/om100978w

Fuentes B.; Garcia-Melchor, M.; Lledós, A.; Maseras, F.; Casares, J. A.; Ujaque, G.; Espinet. P.
“Palladium Round Trip in the Negishi Coupling of trans- [PdMeCl(PMePh2)2] with ZnMeCl. An Experimental and DFT Study of the Transmetallation Step.”
Chem. Eur. J., 201016, 8596-8599.

Salas, G.; Casares, J. A.; Espinet, P.
“Enthalpy of Ligand Substitution in cis Organopalladium Complexes with Monodentate Ligands.”
Dalton Trans2009, 39, 8413-8420. DOI: 10.1039/B910055E

Carrera, N.; Pérez-Temprano, M.H.; Albéniz, A. C.; Casares, J. A.; Espinet, P.
”A Convenient Quick Synthesis of SnBu2RCl Derivatives.”
Organometallics2009, 28, 3957-3958. DOI: 10.1021/om900326g

Martín Pérez-Rodríguez, Ataualpa A. C. Braga, Max Garcia-Melchor, Mónica H. Pérez-Temprano, Juan A. Casares, Gregori Ujaque, Angel R. de Lera, Rosana Álvarez, Feliu Maseras, Pablo Espinet.
“The C-C Reductive Elimination in Palladium Complexes, and the Role of Coupling Additives. A DFT Study Supported by Experiment.”
J. Am. Chem. Soc2009131, 3650-3657

Mónica H. Pérez-Temprano, Ainara Nova, Juan A. Casares, Pablo Espinet.
“Observation of a hidden intermediate in the Stille reaction. Study of the reversal of the transmetalation step.”
J Am. Chem. Soc. 2008130,32, 10518-10519.