RT Journal Article
T1 Rhodium(III)-Catalyzed Formal Cycloaddition between Thienopyridine/Thienopyrazine Carboxylic Acids and Alkynes, Triggered by C−H Activation
A1 Rodrigues, Juliana M.
A1 Cendón Mariño, Borja
A1 Gulías Costa, Moisés
A1 Mascareñas Cid, José Luis
A1 Queiroz, Maria João
K1 Annulation
K1 C−H Activation
K1 N,S-heterocycles
K1 Rhodium catalysis
K1 Tricyclic ɑ-pyrones
AB In the last decade, a number of metal-catalyzed technologies for the functionalization of C−H bonds in carbonaceous aromatic substrates have been developed. However, similar reactions with aza-heteroaromatic precursors are more challenging and have been much less developed. Herein, we report for the first time catalytic formal cycloadditions of N,S-heterocycles featuring carboxylic acid substituents, with unsaturated partners (alkynes). The reaction, which works with different symmetrical and unsymmetrical alkynes, produces appealing tricyclic ɑ-pyrones in a straightforward manner. The optimized conditions established for a model reaction employing thieno[2,3-b]pyridine-2-carboxylic acid as substrate, involved the use of Ag2CO3/AgSbF6 as additives, and proved to be general for different alkynes. Moreover, analogous cycloadditions using thieno[3,2-b]pyridine-2-carboxylic acid and thieno[2,3-b]pyrazine-6-carboxylic acid were successfully developed. Overall, this catalytic technology allows to build, in a single step, an interesting variety of pharmaceutically relevant tricyclic ɑ-pyrones exhibiting nitrogen and sulfur heteroatoms
PB Wiley
YR 2021
FD 2021
LK http://hdl.handle.net/10347/26595
UL http://hdl.handle.net/10347/26595
LA eng
NO J. M. Rodrigues, B. Cendón, M. Gulías, J. L. Mascareñas, M.-J. R. P. Queiroz, Eur. J. Org. Chem. 2021, 2021, 3234.
NO This is the peer reviewed version of the following article: J. M. Rodrigues, B. Cendón, M. Gulías, J. L. Mascareñas, M.-J. R. P. Queiroz, Eur. J. Org. Chem. 2021, 2021, 3234, which has been published in final form at https://doi.org/10.1002/ejoc.202100439. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions
NO To Fundação para a Ciência e Tecnologia (FCT) – Portugal financially supports CQUM (UID/QUI/686/2020), also financed by European Regional Development Fund (ERDF), COMPETE2020 and Portugal2020, the PT NMR network also supported by Portugal2020 and the PhD grant of J.M.R. (SFRH/BD/115844/2016) also financed by ESF (European Social Fund – North Portugal Regional Operational Programme) and HCOP (Human Capital Operational Programme). To COST Action CA15106 – C−H Activation in Organic Synthesis (CHAOS) – including a Short-Term Scientific Mission (STSM) grant attributed to J.M.R. to work in CiQUS. We also thank Spanish grants SAF2016-76689-R, PID2019-108624RB-I00, PID2019-110385GB-I00 and FPI fellowship BES-2017-079784 to B.C., the Consellería de Cultura, Educación e Ordenación Universitaria (ED431C 2017/19, 2015-CP082 and Centro Singular de Investigación de Galicia accreditation 2019–2022, ED431G 2019/03, the European Regional Development Fund (ERDF), and the European Research Council (Advanced Grant No. 340055)
DS Minerva
RD 23 abr 2026