XVIII Simposio de Jóvenes Investigadores Químicos de la RSEQ
Sevilla, 21 – 28 noviembre
– Oral: · Metal-free synthesis of 3-trifluoromethypyrazoles: [3+2] cyclization of styrenes and 2,2,2-trifluorodiazoethane Julia Altarejos, David Sucunza, Juan J. Vaquero, Estíbaliz Merino, and Javier Carreras
– Póster: · Visible-light mediated synthesis of indazoles Clara Mañas, Estíbaliz Merino
– Póster: · Synthesis of novel five membered organoborate heterocycles and their use in cross-coupling reactions Isabel Valencia, Patricia Garcia-Garcia, David Sucunza, Adrián Pérez-Redondo, Juan J. Vaquero
Treatment of various vinylbenzopyridines with allyl(dichloro)borane affords five-membered organoborate heterocycles via a metal-free carboboration. The reaction between these organoborates and Grignard reagents increases the number of derivatives belonging to this novel family of four-coordinate organoboron compounds. Some of them were used as reagents in phenylations and methylations in moderate to high yields under standard palladium-catalyzed cross-coupling reaction conditions.
Gold(I)-catalyzed cyclization of o-alkenyl-o’-alkynylbiaryls in the presence of external or internal nucleophiles provides a straightforward access to phenanthrene-based polycycles, which are of considerable interest in materials science. Thus, their reactions with alcohols yield functionalized dihydrophenanthrenes, in a process that can also be carried out intramolecularly to provide phenanthrene-derived heteropolycyclic compounds. Moreover, benzo[b]triphenylenes can be synthesized from o-methoxyvinyl-o’-alkynylbiaryls, in a reaction in which an (hetero)aryl substituent at the triple bond acts as an internal nucleophile.
Highly efficient unbridged D-A+(D) chromophores based on the quinolizinium cation for nonlinear optical (NLO) applications
Esmeralda Sánchez-Pavón, Javier Recio, Marco Antonio Ramirez, Belen Batanero, Koen Clays, Francisco Mendicuti, Gema Marcelo, Thais Carmona, Obis Castaño, Silvia Angelova, Jose L. Andres, Juan J. Vaquero, Ana M. Cuadro*
Novel charged D-A+ chromophores based on quinolizinium cations as acceptor unit have been prepared by treating haloquinolizinium salts with N-heteroarylstannanes under Stille reaction conditions. This approach provides an easy access to potential one-dimensional D-A+ and two-dimensional D-A+-D chromophores in which the acceptor moiety (A+) is the simple azonia cation and the donors are different π-rich N-heterocycles. The first hyperpolarizabilities (β) were measured by hyper-Rayleigh scattering experiments and the experimental data confirmed that the inherent polarization between donor and acceptor fragments modulates the NLO properties. The electronic structures and properties (including both the linear and nonlinear optical properties) of the quinolizinium chromophores were examined by theoretical (DFT, HF and MP2) calculations. A promising strategy for the rational design of D-A building blocks to create new organic-based NLO materials is proposed..
Reaction of BCl3 with suitably substituted o-alkynylanilines promotes a cascade reaction in which BN-polycyclic compounds are obtained via the formation of two new cycles and three new bonds in a single operational step. The reaction is highly efficient and takes place at room temperature, providing a very mild and straightforward strategy for the preparation of BN-aromatic compounds, which can be further transformed into a variety of BN-PAHs with different polycyclic cores and substituents.
The synthesis of organoboron compounds have attracted the attention of the synthetic community. In particular, molecules with C(sp2)-B bonds enable the transformation to new C−C or C-heteroatom bonds by well-established methodologies. Alkenyl boronates have the possibility for further conversion of the boron moiety or functionalization of the double bond. This review gives an overview on the recent methodologies for the selective preparation of the challenging highly substituted alkenyl boronates from alkynes.
– Póster: · Photocatalytic synthesis of indazoles from alkynylazobenzenes Clara Mañas, Estíbaliz Merino
– Póster: · Metal-free synthesis of medium-sized rings by cationic carbocyclization of trienynes Jaime Tostado Sánchez, Ana Milián, Juan J. Vaquero, Manuel A. Fernández-Rodríguez
XXXVIII Reunión Bienal de la Real Sociedad Española de Química (RSEQ)
Granada, 27-30 June
– Oral: · Asymmetric Photocatalysis Through Smiles Rearrangements Estíbaliz Merino
– Oral: · Drogas, fármacos y venenos: el impacto de los productos naturales en la historia David Sucunza
– Póster: · Progress towards the synthesis of Laetevirenol A Lucía Sánchez Jiménez, Ana Milián, Jaime Tostado, Juan J. Vaquero, Patricia García García, Manuel A. Fernández Rodríguez
– Póster: · Gold(I) catalyzed cyclization of alkynylcyclobutanamides towards lactams Guillermo G. Otárola, María Soledad Garre, Estíbaliz Merino, David Sucunza, Juan J. Vaquero, Patricia García-García
– Póster: · Catalytic (enantioselective) access to 4-(sec-alkyl)anilines via 1,6-conjugate addition of Grignard reagents to in situ generated aza-p-quinone methides Mercedes Zurro, L. Ge, S. R. Harutyunyan
XXVIII REUNIÓN BIENAL del Grupo Especializado de Química Orgánica
Granada, 1 July
– Póster: · Photocatalytic synthesis of a-chloro- and a-hydroxy b-sulfonylamides. Preparation of anticancer drug Bicalutamide
Sergio Torres, Mercedes Zurro, Estíbaliz Merino
– Póster: · Preparation of 5-aryl-3-trifluoromethylpyrazoles: one-pot metal-free transformation from styrenes and 2,2,2-trifluorodiazoethane
Julia Altarejos, David Sucunza, Juan José Vaquero, Estíbaliz Merino, Javier Carreras
Patricia García-García ha publicado su primer Angewandte Chemie como autora de correspondencia:
Metal-Free Temperature-Controlled Regiodivergent Borylative Cyclizations of Enynes: BCl3-Promoted Skeletal Rearrangement: A. Milián, M. A. Fernández-Rodríguez, E. Merino, J. J. Vaquero, P. García-García, Angew. Chem. Int. Ed.2022, doi.org/10.1002/anie.202205651.
Metal-free borylative cyclization of biphenyl-embedded 1,3,5-trien-7-ynes in the presence of simple and inexpensive BCl3 provided synthetically useful borylated building blocks. The outcome of the process depends on the reaction temperature, with borylated phenanthrenes obtained at 60 ºC and phenanthrene-fused borylated cyclobutanes formed at 0 ºC. Based on DFT calculations, a mechanism for these novel transformations has been proposed, which involves an uncommon skeletal rearrangement, including migration of a methyl group and alkyne fragmentation, unprecedented in BCl3-promoted cyclization reactions.