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Víctor Varela-Izquierdo Dr. Ana M. Geer Prof. Dr. Bas de Bruin Dr. José A. López Prof. Dr. Miguel A. Ciriano Dr. Cristina Tejel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(69):15915-15928
The feasibility of oxidative addition of the P−H bond of PHPh2 to a series of rhodium complexes to give mononuclear hydrido-phosphanido complexes has been analyzed. Three main scenarios have been found depending on the nature of the L ligand added to [Rh(Tp)(C2H4)(PHPh2)] (Tp= hydridotris(pyrazolyl)borate): i) clean and quantitative reactions to terminal hydrido-phosphanido complexes [RhTp(H)(PPh2)(L)] (L=PMe3, PMe2Ph and PHPh2), ii) equilibria between RhI and RhIII species: [RhTp(H)(PPh2)(L)]⇄[RhTp(PHPh2)(L)] (L=PMePh2, PPh3) and iii) a simple ethylene replacement to give the rhodium(I) complexes [Rh(κ2-Tp)(L)(PHPh2)] (L=NHCs-type ligands). The position of the P−H oxidative addition–reductive elimination equilibrium is mainly determined by sterics influencing the entropy contribution of the reaction. When ethylene was used as a ligand, the unique rhodaphosphacyclobutane complex [Rh(Tp)(η1-Et)(κC,P-CH2CH2PPh2)] was obtained. DFT calculations revealed that the reaction proceeds through the rate limiting oxidative addition of the P−H bond, followed by a low-barrier sequence of reaction steps involving ethylene insertion into the Rh−H and Rh−P bonds. In addition, oxidative addition of the P−H bond in OPHPh2 to [Rh(Tp)(C2H4)(PHPh2)] gave the related hydride complex [RhTp(H)(PHPh2)(POPh2)], but ethyl complexes resulted from hydride insertion into the Rh−ethylene bond in the reaction with [Rh(Tp)(C2H4)2]. 相似文献
994.
Marta M.P.S. Neves Henri P.A. Nouws Cristina Delerue-Matos Daniel Martín-Yerga 《Current Opinion in Electrochemistry》2020
The incorporation of engineered nanoparticles in commercial products and industrial processes has broadly increased in recent years, which raises concerns about their environmental impact. In this review, we present electrochemistry as a promising analytical tool towards the detection and characterization of nanoparticles for environmental purposes. Recent research has not only demonstrated the applicability of electrochemical methods for the quantification of nanoparticles in environmental samples, but also for the study of properties and transformations of nanoparticles. All these aspects are very relevant to understand their toxicity in the environment. In this context, we discuss several electrochemical methods to quantify and study the size and shape, surface properties, interparticle interactions, chemical reactivity and speciation of nanoparticles. 相似文献
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Dr. Simone Ghinato Dr. Davide Territo Prof. Andrea Maranzana Prof. Vito Capriati Dr. Marco Blangetti Prof. Cristina Prandi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(8):2868-2874
We report that the nucleophilic acyl substitution reaction of aliphatic and (hetero)aromatic amides by organolithium reagents proceeds quickly (20 s reaction time), efficiently, and chemoselectively with a broad substrate scope in the environmentally responsible cyclopentyl methyl ether, at ambient temperature and under air, to provide ketones in up to 93 % yield with an effective suppression of the notorious over-addition reaction. Detailed DFT calculations and NMR investigations support the experimental results. The described methodology was proven to be amenable to scale-up and recyclability protocols. Contrasting classical procedures carried out under inert atmospheres, this work lays the foundation for a profound paradigm shift of the reactivity of carboxylic acid amides with organolithiums, with ketones being straightforwardly obtained by simply combining the reagents under aerobic conditions and with no need of using previously modified or pre-activated amides, as recommended. 相似文献
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Leite Irena Andrianov Victor Zelencova-Gopejenko Diana Loza Einars Kazhoka-Lapsa Iveta Domracheva Ilona Stoyak Marta Chlopicki Stefan Kalvins Ivars 《Chemistry of Heterocyclic Compounds》2021,57(11):1086-1106
Chemistry of Heterocyclic Compounds - Acyl derivatives of aziridine-2-carboxylic acid have been synthesized and tested as PDIA1 inhibitors. Calculations of charge value and distribution in... 相似文献
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Prof. Gabriella Salviulo Prof. Maria Cristina Lavagnolo Prof. Manuele Dabalà Prof. Enrico Bernardo Prof. Antonino Polimeno Prof. Mauro Sambi Prof. Franco Bonollo Prof. Silvia Gross 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(22):6676-6695
Circular economy is considered a new chance to build a more sustainable world from both the social and the economic point of view. In this Essay, the possible contribution of inorganic chemistry towards a smooth transition to circularity in inorganic materials design and production is discussed by adopting an interdisciplinary approach. 相似文献
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