Dra. Leyre Marzo, “Ramón y Cajal” Researcher at Organic Chemistry Department of the Universidad Autónoma de Madrid (Madrid) Fotocatálisis como herramienta sintética para la formación de nuevos enlaces C-C
Room 0.6, Edificio Polivalente, UAH. May 24th, 12.00.
A Brønsted acid catalyzed cyclization of o-alkenyl-o′-alkynylbiaryls for the synthesis of biologically relevant dibenzo-fused medium-sized rings has been developed. The outcome of the cyclization is determined by the nature of the substituent at the alkyne, with arenes favoring seven-membered rings and alkyl substituents producing eight-membered rings. These reactions proceed via a vinyl cation, which is captured by water and, notably, by C-nucleophiles, such as electron-rich (hetero)arenes.
On April 12th, Álvaro González Molina successfully defended his doctoral thesis under the supervision of Dr. Jose Luis Aceña Bonilla and Prof. Juan José Vaquero: “Síntesis de aminoácidos bicíclicos y peptidomiméticos conformacionalmente restringidos derivados de prolina y ácido pipecólico”
Thanks to all members of the tribunal: Dr. Javier García Marín, Dr. Ángela Martín-Serrano Ortiz and Dr. María Sánchez Roselló
On April 4th, Clara Mañas successfully defended her doctoral thesis under the supervision of Dr. Estíbaliz Merino: “Design and study of novel reactivities of alkynylazobenzenes”
Thanks to all members of thesis tribunal: Dr. Teresa Quirós, Dr. Eva Maya and Dr. María Ribagorda
Asymmetric, Remote C(sp3)−H Arylation via Sulfinyl-Smiles Rearrangement
Yawen Hu, Cédric Hervieu, Dr. Estíbaliz Merino*, Prof. Cristina Nevado*
Angew. Chem. Int. Ed. 2024, Early View
DOI: anie.202319158
An efficient asymmetric remote arylation of C(sp3)−H bonds under photoredox conditions is described here. The reaction features the addition radicals to a double bond followed by a site-selective radical translocation (1,n-hydrogen atom transfer) as well as a stereocontrolled aryl migration via sulfinyl-Smiles rearrangement furnishing a wide range of chiral α-arylated amides with up to >99 : 1 er. Mechanistic studies indicate that the sulfinamide group governs the stereochemistry of the product with the aryl migration being the rate determining step preceded by a kinetically favored 1,n-HAT process.
We disclose the heterodifunctionalization of alkynylazobenzenes promoted exclusively by visible light in the absence of any transition metal and/or photocatalyst. This reaction features excellent regioselectivity on a broad variety of substrates with perfect atom economy. Alcohols, carboxylic acids, thiols, amides, heterocycles, and even water are suitable substrates for the promotion of the oxyamination, sulfenoamination, and diamination reactions. In this manner, biologically active indazole scaffolds can be rapidly assembled from alkyne feedstocks.