Joint ITC and DFT Study of the Affinity of Some Lewis Bases to HIFP in Solution

HFIP, i.e. 1,1,1,3,3,3-hexafluoropropan-2-ol, was found to be an exceptional medium,[1] either as solvent or co-solvent, that allows many reactions to occur.[2-5] However, the exact role and mode of action of HFIP in various chemical transformations still remains elusive. Despite many reports dealing with water/HFIP complexes, little has been published on other molecular complexes of HFIP as well as on thermochemistry of the formation of such complexes.[6] Within this study the affinity of a series of eight different Lewis bases (3 sulfoxides, 3 Nsp2 pyridine derivatives, 1 aromatic amine, 1 cyclic aliphatic ether) to HFIP (as Lewis acid) is investigated experimentally by Isothermal Titration Calorimetry (ITC) and theoretically using static DFT-D calculations. Measured ITC association enthalpy values ΔHaITC spanned -9.3 kcal/mol - -14 kcal/mol. Computations including a PCM implicit solvation model produced similar exothermicity of association of all studied systems - ΔHa values ranging -8.5 – -12.7 kcal/mol. In general, most of interaction energy is due to the hydrogen bonding and not due to formation of significantly strong halogen bonds. An additional set of calculations combining implicit and explicit solvation by chlorobenzene of the reactants, pointed out the relatively low interference of the solvent with the HFIPbase complexation, which main effect is to slightly enhance the Gibbs energy of the HFIP-Lewis base association. It is speculated that the interactions of bulk HFIP with Lewis bases therefore may significantly intervene in catalytic processes not only via the dynamic miscrostructuration of the medium but also more explicitly by affecting bonds’ polarization at the Lewis bases

Copper-catalyzed functionalization of enynes.

From Europe PMC via Jisc Publications RouterHistory: ppub 2020-10-01, epub 2020-10-07Publication status: PublishedFunder: Engineering and Physical Sciences Research Council; Grant(s): EP/P001386/1, EP/M005062/1The copper-catalyzed functionalization of enyne derivatives has recently emerged as a powerful approach in contemporary synthesis. Enynes are versatile and readily accessible substrates that can undergo a variety of reactions to yield densely functionalized, enantioenriched products. In this perspective, we review copper-catalyzed transformations of enynes, such as boro- and hydrofunctionalizations, copper-mediated radical difunctionalizations, and cyclizations. Particular attention is given to the regiodivergent functionalization of 1,3-enynes, and the current mechanistic understanding of such processes

Supplementary data for the article: Milovanović, M. R.; Dherbassy, Q.; Wencel‐Delord, J.; Colobert, F.; Zarić, S. D.; Đukić, J.-P. The Affinity of Some Lewis Bases for Hexafluoroisopropanol as a Reference Lewis Acid: An ITC/DFT Study. ChemPhysChem 2020, 21 (18), 2136–2142. https://doi.org/10.1002/cphc.202000560.

Supplementary material for: [https://doi.org/10.1002/cphc.202000560]Related to published version: [https://cherry.chem.bg.ac.rs/handle/123456789/4337]Related to accepted version: [https://cherry.chem.bg.ac.rs/handle/123456789/4339

Enantioselective Copper‐Catalyzed Borylative Cyclization for the Synthesis of Quinazolinones

From Wiley via Jisc Publications RouterHistory: received 2021-03-05, pub-electronic 2021-05-19Article version: VoRPublication status: PublishedFunder: Leverhulme Trust; Id: http://dx.doi.org/10.13039/501100000275; Grant(s): RPG-2016-360Funder: Horizon 2020 Framework Programme; Id: http://dx.doi.org/10.13039/100010661; Grant(s): 798846-CuCANAbstract: Quinazolinones are common substructures in molecules of medicinal importance. We report an enantioselective copper‐catalyzed borylative cyclization for the assembly of privileged pyrroloquinazolinone motifs. The reaction proceeds with high enantio‐ and diastereocontrol, and can deliver products containing quaternary stereocenters. The utility of the products is demonstrated through further manipulations

Axial chirality control by means of C-H activation : towards natural molecules and original ligands

La chiralité axiale est une propriété importante de composés biologiquements actifs, de matériaux avancés et plus particulièrement de ligands utilisés en catalyse asymétrique. En effet de nombreuses structures biaryliques atropisomériques ont montré un excellent pouvoir d’induction asymétrique. Ainsi le contrôle de l’atropisomérie et le développement de nouvelles méthodes synthétiques permettant la synthèse de composés à chiralité axiale optiquement purs attire l’attention de la communauté scientifique. Au cours de ce travail une nouvelle stratégie vers l’obtention de biaryles à chiralité axiale atropenrichis a été explorée. L’utilisation de sulfoxydes énantiopurs, jouant à la fois le rôle de groupe directeur et d’auxiliaire de chiralité, dans une stratégie de fonctionnalisation de liaisons C-H par catalyse homogène au palladium, a permis l’obtention efficace de nombreux composés biaryliques hautement atropenrichis . Les méthodologies développées ont ensuite été appliquées à la synthèse formelle d’un composé naturel bioactif à chiralité axiale, la (-)-steganone, ainsi qu’à la synthèse de ligands doublement atropisomériques inédits.Axial chirality is an important property of biologically active compounds, advanced materials and more importantly of ligands used in asymmetric catalysis. Indeed, numerous atropisomeric biaryls have demonstrated an excellent asymmetric induction capacity. Thus, the control of atropisomery and the development of original synthetic methodologies allowing the synthesis and the obtention of optically pure axially chiral compounds is an important goal for the scientific community. In this work, a new strategy for the synthesis of atropenriched axially chiral biaryls was explored. The use of enantiopur sulfoxides playing the role of both, a directing group and a chirality auxiliary, in a palladium catalyzed C-H functionalization, allowed the efficient construction of numerous highly atropenriched biaryl compounds. The developed methodologies were furthermore applied to the formal synthesis of an axially chiral and bioactive compound, (-)-steganone, as well as the synthesis of doubly atropisomeric unprecedented ligands. These ligands displayed an excellent potential for asymmetric induction in homogenous asymmetric hydrogenation

Contrôle de la chiralité axiale par activation de liaisons C-H : accès à des molécules naturelles et ligands inédits

Axial chirality is an important property of biologically active compounds, advanced materials and more importantly of ligands used in asymmetric catalysis. Indeed, numerous atropisomeric biaryls have demonstrated an excellent asymmetric induction capacity. Thus, the control of atropisomery and the development of original synthetic methodologies allowing the synthesis and the obtention of optically pure axially chiral compounds is an important goal for the scientific community. In this work, a new strategy for the synthesis of atropenriched axially chiral biaryls was explored. The use of enantiopur sulfoxides playing the role of both, a directing group and a chirality auxiliary, in a palladium catalyzed C-H functionalization, allowed the efficient construction of numerous highly atropenriched biaryl compounds. The developed methodologies were furthermore applied to the formal synthesis of an axially chiral and bioactive compound, (-)-steganone, as well as the synthesis of doubly atropisomeric unprecedented ligands. These ligands displayed an excellent potential for asymmetric induction in homogenous asymmetric hydrogenation.La chiralité axiale est une propriété importante de composés biologiquements actifs, de matériaux avancés et plus particulièrement de ligands utilisés en catalyse asymétrique. En effet de nombreuses structures biaryliques atropisomériques ont montré un excellent pouvoir d’induction asymétrique. Ainsi le contrôle de l’atropisomérie et le développement de nouvelles méthodes synthétiques permettant la synthèse de composés à chiralité axiale optiquement purs attire l’attention de la communauté scientifique. Au cours de ce travail une nouvelle stratégie vers l’obtention de biaryles à chiralité axiale atropenrichis a été explorée. L’utilisation de sulfoxydes énantiopurs, jouant à la fois le rôle de groupe directeur et d’auxiliaire de chiralité, dans une stratégie de fonctionnalisation de liaisons C-H par catalyse homogène au palladium, a permis l’obtention efficace de nombreux composés biaryliques hautement atropenrichis . Les méthodologies développées ont ensuite été appliquées à la synthèse formelle d’un composé naturel bioactif à chiralité axiale, la (-)-steganone, ainsi qu’à la synthèse de ligands doublement atropisomériques inédits

Axial chirality control by means of C-H activation : towards natural molecules and original ligands

La chiralité axiale est une propriété importante de composés biologiquements actifs, de matériaux avancés et plus particulièrement de ligands utilisés en catalyse asymétrique. En effet de nombreuses structures biaryliques atropisomériques ont montré un excellent pouvoir d’induction asymétrique. Ainsi le contrôle de l’atropisomérie et le développement de nouvelles méthodes synthétiques permettant la synthèse de composés à chiralité axiale optiquement purs attire l’attention de la communauté scientifique. Au cours de ce travail une nouvelle stratégie vers l’obtention de biaryles à chiralité axiale atropenrichis a été explorée. L’utilisation de sulfoxydes énantiopurs, jouant à la fois le rôle de groupe directeur et d’auxiliaire de chiralité, dans une stratégie de fonctionnalisation de liaisons C-H par catalyse homogène au palladium, a permis l’obtention efficace de nombreux composés biaryliques hautement atropenrichis . Les méthodologies développées ont ensuite été appliquées à la synthèse formelle d’un composé naturel bioactif à chiralité axiale, la (-)-steganone, ainsi qu’à la synthèse de ligands doublement atropisomériques inédits.Axial chirality is an important property of biologically active compounds, advanced materials and more importantly of ligands used in asymmetric catalysis. Indeed, numerous atropisomeric biaryls have demonstrated an excellent asymmetric induction capacity. Thus, the control of atropisomery and the development of original synthetic methodologies allowing the synthesis and the obtention of optically pure axially chiral compounds is an important goal for the scientific community. In this work, a new strategy for the synthesis of atropenriched axially chiral biaryls was explored. The use of enantiopur sulfoxides playing the role of both, a directing group and a chirality auxiliary, in a palladium catalyzed C-H functionalization, allowed the efficient construction of numerous highly atropenriched biaryl compounds. The developed methodologies were furthermore applied to the formal synthesis of an axially chiral and bioactive compound, (-)-steganone, as well as the synthesis of doubly atropisomeric unprecedented ligands. These ligands displayed an excellent potential for asymmetric induction in homogenous asymmetric hydrogenation

Asymmetric C–H activation as a modern strategy towards expedient synthesis of steganone

International audienc