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The bulky 2,5-dimethylthiophene (2,5-Me2T) reacts at 60 degrees C with TpMe2Ir(C2H4)2 to give a mixture of two TpMe2Ir(III) hydride products, 3 and 4, that contain in addition a thienyl (3) or a thienyl-derived ligand (4). For the generation of 3 only sp2 C-H activation is needed, but the formation of 4 requires also the activation of an sp3 C-H bond and the formation of a new C-C bond (between vinyl and thienyl fragments). In the presence of 2,5-Me2T, compound 4 reacts further to produce a complex thiophenic structure (5, characterized by X-ray methods) that derives formally from two molecules of 2,5-Me2T and a vinyl fragment. Compounds 3-5 can be readily protonated by [H(OEt2)2][BAr'4](Ar'= 3,5-C6H3(CF3)2), with initial generation of carbene ligands (in the case of 3 and 5) as a consequence of H+ attack at the beta-carbon of the Ir-thienyl unit. Free, substituted thiophenes, derived from the original 2,5-Me2T, may be isolated in this way.
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http://dx.doi.org/10.1039/b419414d | DOI Listing |
Chem Sci
August 2025
College of Chemistry and Materials Science, Key Laboratory of Chemical Biology of Hebei Province, Hebei Research Center of the Basic Discipline of Synthetic Chemistry, Institute of Life Science and Green Development Hebei University Baoding Hebei 071002 P. R. China
The photocatalytic oxidative dipolar [3 + 2] cycloaddition reaction is a promising green approach for producing pyrrolo[2,1-]isoquinolines. However, developing sustainable cycloaddition methods with heterogeneous photocatalysts is still in its infancy, largely owing to their low reactivity and photostability. Herein, we propose a charge-oxygen synergy strategy through a dual-engineered covalent organic framework (COF) by integrating π-spacers with donor-acceptor motifs to promote intermolecular cycloaddition.
View Article and Find Full Text PDFActa Crystallogr E Crystallogr Commun
September 2025
Department of Chemistry, Taras Shevchenko National University of Kyiv, Volodymyrska Street 64, Kyiv, 01601, Ukraine.
The unit cell of the title compound, [Ni(CHNO)]·2CHOH, consists of a neutral complex and two methanol mol-ecules. In the complex, the two tridentate 2-[3-(benzo[][1,3]dioxol-5-yl)-1-1,2,4-triazol-5-yl]-6-(1-pyrazol-1-yl)pyridine ligands coordinate to the central Ni ion through nitro-gen atoms of the pyrazole, pyridine and triazole groups, forming a pseudo-octa-hedral coordination sphere. Neighbouring mol-ecules are linked through weak C-H(pz)⋯π(ph) inter-actions into monoperiodic chains, which are further linked through weak C-H⋯H/N/C inter-actions into diperiodic layers.
View Article and Find Full Text PDFJ Phys Chem A
September 2025
Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284, United States.
Ionization of alkanes to form radical cations activates their otherwise unreactive C-H bonds, facilitating important chemical processes such as hydrocarbon cracking. This work investigates the radical cation dissociation dynamics of hexane (CH) structural isomers by using femtosecond time-resolved mass spectrometry and quantum chemical calculations. All five isomers exhibit competition between the yields of fragment ions arising from direct C-C bond cleavage or dissociative rearrangement with hydrogen migration on dynamical time scales of ∼50-300 fs, suggesting that hydrogen migration in the metastable cations operates on such short time scales.
View Article and Find Full Text PDFInorg Chem
September 2025
Henan Key Laboratory of Polyoxometalate Chemistry, College of Chemistry and Molecular Sciences, Henan University, Kaifeng, Henan 475004, China.
Selective oxidation of benzylic C(sp)-H bonds to ketones is critical to the production of fine chemicals but typically requires toxic/precious metal catalysts under harsh conditions. While iron-based complexes have recently served as catalysts for photocatalytic C-H bond activation, most systems operate via homogeneous catalysis. Developing a light-driven strategy under visible light with O as an oxidant is of major importance.
View Article and Find Full Text PDFJ Am Chem Soc
September 2025
State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Chang Ping, Beijing 102249, China.
The dynamic structural evolution of heterogeneous catalysts is a ubiquitous phenomenon that has attracted a lot of interest. Catalyst reconstruction can occur after appropriate pretreatment, resulting in more efficient active catalysts, which is an attractive but challenging issue. Here, we reveal a CO activation strategy that controls the microenvironment of the Co sites in the high-silica Co-ZSM-5 catalyst (denoted as 0.
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