1,507 research outputs found
Supplementary data for the article: MilovanoviÄ, M. R.; Dherbassy, Q.; WencelâDelord, J.; Colobert, F.; ZariÄ, S. D.; ÄukiÄ, J.-P. The Affinity of Some Lewis Bases for Hexafluoroisopropanol as a Reference Lewis Acid: An ITC/DFT Study. ChemPhysChem 2020, 21 (18), 2136â2142. 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
Late stage CâH activation of a privileged scaffold; synthesis of a library of benzodiazepines
A library of over twenty 5-(2-arylphenyl)-1,3-dihydro-2H-1,4-benzodiazepin-2-ones has been formed by a microwave-mediated late-stage palladium-catalysed arylation of 1,4-benzodiazepines using diaryliodonium salts. This can also be applied to nordazepam (7-chloro-5-phenyl-1,3-dihydro-2H-1,4-benzodiazepin-2-one), the active metabolite of diazepam, and subsequent N-alkylation and/or H/D exchange allows further diversification towards elaborated pharmaceuticals and their 3,3'-deuterated analogues
Increasing Catalyst Efficiency in CâH Activation Catalysis
CâH activation reactions with high catalyst turnover numbers are still very rare in the literature and 10 mol % is a common catalyst loading in this field. We offer a representative overview of efficient CâH activation catalysis to highlight this neglected aspect of catalysis development and inspire future effort towards more efficient CâH activation. Examples ranging from palladium catalysis, Cp*Rh III - and Cp*Co III -catalysis, the CâH borylation and silylation to methane CâH activation are presented. In these reactions, up to tens of thousands of catalyst turnovers have been observed
Cp*Co(III)-Catalyzed coupling of benzamides with α,ÎČ-unsaturated carbonyl compounds: Preparation of aliphatic ketones and azepinones
A Cp*Co(III)-catalyzed C-H functionalization of benzamide substrates with α,ÎČ-unsaturated ketones has been optimized, providing a facile route towards aliphatic ketone products. When employing α,ÎČ-unsaturated aldehydes as coupling partners, under the optimized protocol, a cascade reaction forming azepinones has also been developed. Finally, DFT studies have demonstrated how stabilization of a metallo-enol intermediate when employing α,ÎČ-unsaturated ketones is the driving force leading to the observed aliphatic ketone product rather than olefinic products reported using α,ÎČ-unsaturated esters as coupling partners
Iridium(I)-Catalyzed Intramolecular Hydrocarbonation of Alkenes: Efficient Access to Cyclic Systems Bearing Quaternary Stereocenters
This is the peer reviewed version of the following article: David FernĂĄndez, MoisĂ©s GulĂas, JosĂ© L.
Mascareñas, Fernando López (2017), Iridium (I)-Catalyzed Intramolecular Hydrocarbonation of Alkenes:
Efficient Access to Cyclic Systems Bearing Quaternary Stereocenters, Angew. Chem. Int. Ed., 56, 9541-9545
[doi: 10.1002/anie.201705105]. This article may be used for non-commercial purposes in accordance with Wiley
Terms and Conditions for self-archivingA catalytic, versatile and atom-economical CâH functionalization process that provides a wide variety of cyclic systems featuring methyl-substituted quaternary stereocenters is described. The method relies on the use of a cationic IrIâbisphosphine catalyst, which promotes a carboxamide-assisted activation of an olefinic C(sp2)âH bond followed by exo-cyclization to a tethered 1,1-disubstituted alkene. The extension of the method to aromatic and heteroaromatic CâH bonds, as well as developments on an enantioselective variant, are also describedThis work has received financial support from the spanish MINECO grants (SAF2016-76689-R, CTQ2016-77047-P), Xunta de Galicia (GRC2013-041, 2015-CP082 and Centro Singular de InvestigaciĂłn de Galicia accreditation 2016â2019 ED431G/09), the European Union (European Regional Development Fund â ERDF) and ERC (Adv. Grant No. 340055). D.F.F. thanks the MINECO for a fellowship. The Orfeo-Cinqa network CTQ2014-51912-REDC is kindly acknowledgedS
Combining C-H functionalisation and flow photochemical heterocyclic metamorphosis (FP-HM) for the synthesis of benzo[1,3]oxazepines
C-H Activation/functionalisation and Flow Photochemical Heterocyclic Metamorphosis (FP-HM) have been combined to synthesize a library of benzo[1,3]oxazepines, a rarely described heterocyclic family. This combined protocol allows
a range of arylated products to be made from simple starting materials, and the cheap flow photochemical system has proven
effective for rapid synthesis of gram-quantities of benzo[1,3]oxazepines
Synthesis of spirocyclic enones by rhodium-catalyzed dearomatizing oxidative annulation of 2-alkenylphenols with alkynes and enynes
The dearomatizing oxidative annulation of 2-alkenylphenols with alkynes and enynes proceeds with high yields and regioselectivities under Rh(III) catalysis. These reactions are successful using Cu(OAc)2 or air as the stoichiometric oxidant, and provide spirocyclic enones, the basic ring system of which appears in several natural products. Application of this process to the preparation of a highly functionalized tetracycle is also demonstrated
Unravelling the mechanism of cobalt-catalysed remote C-H nitration of 8-aminoquinolinamides and expansion of substrate scope towards 1-naphthylpicolinamide
Previously, an unexpected Co-catalysed remote C-H nitration of 8-aminoquinolinamide compounds was developed. This report provided a novel reactivity for Co and was assumed to proceed through the mechanistic pathway already known for analogous Cu-catalysed remote couplings of the same substrates. In order to shed light into this intriguing, and previously unobserved reactivity for Co, a thorough computational study has now been performed, which has allowed for a full understanding of the operative mechanism. This study demonstrates that the Co-catalysed remote coupling does not occur through the previously proposed Single Electron Transfer (SET) mechanism, but actually operates through a High-Spin Induced Remote Radical Coupling mechanism, through a key intermediate with significant proportion of spin density at the 5- and 7-positions of the aminoquinoline ring. Additionally, new experimental data provides expansion of the synthetic utility of the original nitration procedure towards 1-naphthylpicolinamide which unexpectedly appears to operate via a subtly different mechanism despite having a similar chelate environment
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