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Nuevo artículo, Adv. Synth. Cat. 07.23

β-Functionalization of 4a-aza-8a-boranaphthalene via Iridium-catalyzed C−H Borylation

Isabel Valencia, David Sucunza, Francisco Mendicuti, Patricia García-García,* Juan J. Vaquero

Adv. Synth. Cat. 2023, Accepted Articles
DOI: 10.1002/adsc.202300408

A general method for the functionalization of 4a-aza-8a-boranaphthalene in the position β to the nitrogen atom has been developed. This method is based on a regioselective iridium-catalyzed C−H activation process for the introduction of a boronate group, which can subsequently be transformed into a variety of aryl or alkynyl groups via cross-coupling reactions. Selective mono- or difunctionalization can be achieved by controlling the reaction conditions during the borylation step. The photophysical properties of the obtained 3- or 3,6-substituted BN-naphthalenes have been evaluated, and some of them have been found to be significantly fluorescent, with fluorescence quantum yields up to 0.85.

Participación congresos

23rd Tetrahedron Symposium

Gothenburg, Sweden, 27 – 30 junio

– Póster:
· Visible light as a single reagent to promote new transformations in azobenzenes
Clara Mañas, Estíbaliz Merino

– Póster:
· Synthesis of 5-aryl-3-trifluoromethylpyrazoles: one-pot [3+2] cycloaddition-isomerization-oxidation
Julia Altarejos, Estíbaliz Merino, David Sucunza, Juan José Vaquero, Javier Carreras

– Póster:
· Synthesis of borylated polycycles by metal-free borylative cyclization of enynes
Ana Milián, Ester Sans-Panadés, Marcos Humanes, Cintia Virumbrales, Estíbaliz Merino, Roberto Sanz, Juan J. Vaquero, Manuel A. Fernández-Rodríguez, Patricia García-García

– Póster:
· Ir-Catalyzed C−H Borylation of 4a,8a-Dihydro-4a-Aza-8a-Boranaphthalene
Isabel Valencia, Patricia Garcia-Garcia, David Sucunza, Francisco Mendicuti, Juan J. Vaquero

XXXIX Reunión Bienal de la RSEQ

Zaragoza, 27 – 30 junio

– Póster:
· Visible Light Na2Eosin Y Catalysed Hydroxysulfonylation of Acrylamides. Straightforward Access to Anticancer Drug Bicalutamide
Mercedes Zurro, Sergio Torres-Oya, Estibaliz Merino*

– Póster/Flash:
· BF3-promoted cascade cyclization of biaryl embedded 1,8-enynes
Jaime Tostado, Juan J. Vaquero, Manuel A. Rodríguez

– Póster:
· Synthesis of benzo[1.2.3]triazines by heterocyclization of TOSMIC derivatives
Francisco Maqueda, David Sucunza, José Luis Aceña, Juan José Vaquero

– Póster/Flash:
· Synthesis of polycyclic hydrocarbons by gold-catalyzes tandem formation of 4-, 5- and 7-membered rings
L. Sánchez-Jiménez, A. Gargantiel, P. García-García, M. A. Fernández-Rodríguez

– Póster/Flash:
· Towards new peptide-based compounds: synthesis of a series of novel bicyclic amino acids
Álvaro González-Molina, José Luis Aceña y Juan José Vaquero

– Póster/Flash:
· New photoreactivity of azobenzenes towards complex N-heterocycles
Clara Mañas, Estíbaliz Merino

IX Symposium of Medicinal Chemistry Young Researchers

Santiago de Compostela, 22 junio

· Novel bicyclic amino acids as potential building blocks for new peptidomimetics
Álvaro González-Molina, José Luis Aceña y Juan José Vaquero

Nuevo artículo, ACS Macro Lett. 06.2023

Hyper-Cross-Linked Porous Polymer Featuring B–N Covalent Bonds (HCP-BNs): A Stable and Efficient Metal-Free Heterogeneous Photocatalyst

Sara Señorans, Isabel Valencia, Estíbaliz Merino, Marta Iglesias, Manuel A. Fernández-Rodríguez*, Eva M. Maya*

ACS Macro Lett. 2023, ASAP
DOI: 10.1021/acsmacrolett.3c00217

The first example of a porous polymer containing B–N covalent bonds, prepared from a tetraphene B–N monomer and biphenyl as a comonomer, is reported. It was prepared using the solvent knitting strategy, which allows the connection between the aromatic rings of the two monomers through methylene groups provided by an external cross-linking agent. The new polymer exhibited micromeso porosity with an SBET of 612 m2/g, high thermal stability, and potential properties as a heterogeneous photocatalyst, since it is very active in the aza-Henry coupling reaction (>98% of conversion and selectivity). After the first run, the catalyst improves its photocatalytic activity, shortening the reaction time to only 2 h and maintaining this activity in successive runs. The presence of a radical in this structure that remains stable with successive runs makes it a new type of material with potential applications as a highly stable and efficient photocatalyst.

Nuevo artículo, ChemSusChem 05.23

Mizoroki–Heck Macrocyclization Reactions at 1 M Concentration Catalyzed by Sub-nanometric Palladium Clusters

Francisco Garnes–Portolés, Estíbaliz Merino, Antonio Leyva–Pérez*

ChemSusChem 2023, Accepted Articles
DOI: 10.1002/cssc.202300200

Mizoroki-Heck macrocyclization reactions are carried out at 1M concentration with ligand-free Pd cluster catalysts either in solution or supported on solids. Mechanistic studies unveil the essential role of the fluxional Pd cluster to accommodate, at the same time, the reacting groups, to give the intramolecular vs the intermolecular coupling reaction at this high concentration, enabling (in-flow) solid-catalyzed macrocyclization reactions.

Zurro et al. Synthesis 2023: Visible-Light-Mediated Regioselective Chlorosulfonylation of Acrylamides.

Publicaciones > Zurro et al

Visible-Light-Mediated Regioselective Chlorosulfonylation of Acrylamides.

Resumen

A one-step chlorosulfonylation of acrylamides via a photocatalytic redox process is described. This reaction provides α-chlorosulfonylamides with a quaternary center with high regioselectivity via radical process. It is amenable to a broad range of substrates and the products are obtained in moderate to good yields.

Garre et al. Org Biomol Chem. 2023;21(13):2705-2708. Gold-catalyzed endo-selective cyclization of alkynylcyclobutanecarboxamides: synthesis of cyclobutane-fused dihydropyridones.

Publicaciones > Garre et al

Gold-catalyzed endo-selective cyclization of alkynylcyclobutanecarboxamides: synthesis of cyclobutane-fused dihydropyridones.

1. Universidad de Alcalá (IRYCIS), Departamento de Química Orgánica y Química Inorgánica, Instituto de Investigación Química "Andrés M. del Río" (IQAR), Campus Científico-Tecnológico, Facultad de Farmacia, Autovía A-II, Km 33.1, 28805-Alcalá de Henares, Madrid, Spain.  2. Departamento de Química Orgánica e Inorgánica, Instituto Universitario de Química Organometálica "Enrique Moles", Universidad de Oviedo, C/Julián Clavería, 8, 33006 Oviedo, Spain.

ajuanjose.vaquero@uah.es  bjuanjose.vaquero@uah.es  cjuanjose.vaquero@uah.es  djuanjose.vaquero@uah.es  ejuanjose.vaquero@uah.es  fjuanjose.vaquero@uah.es  gjuanjose.vaquero@uah.es

Abstract

Cyclobutane-fused dihydropyridones can be efficiently synthesized by a completely endo-selective gold-catalyzed cyclization of alkynylcyclobutanes bearing an appended amide, which proceeds under mild conditions. The observed selectivity, which is reversed from that previously observed for the cyclization of related alcohols and acids, is supported by DFT calculations.