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15987 15990 46 ; S ; [EN] Catalytic cross-coupling reactions are fundamental transformations in modern organic synthesis. Traditionally based on single-atom transition metal complex catalysts, the use of sub-nanometre metal clusters with enhanced redox and coordinating properties may lead to more efficient catalysts. Recent developments and potential new directions of catalytic sub-nanometre metal clusters for cross-coupling reactions are briefly discussed here Financial support by the "Severo Ochoa" program, the RETOS program (CTQ2014-55178-R) and the Ramon y Cajal Program by MINECO (Spain), and also by "Convocatoria 2014 de Ayudas Fundacion BBVA a Investigadores y Creadores Culturales" is acknowledged. Leyva Perez, A. (2017). Sub-nanometre metal clusters for catalytic carbon-carbon and carbon-heteroatom cross-coupling reactions. Dalton Transactions. 46(46):15987-15990. https://doi.org/10.1039/c7dt03203j Phan, N. T. S., Van Der Sluys, M., & Jones, C. W. (2006). On the Nature of the Active Species in Palladium Catalyzed Mizoroki–Heck and Suzuki–Miyaura Couplings – Homogeneous or Heterogeneous Catalysis, A Critical Review. Advanced Synthesis & Catalysis, 348(6), 609-679. doi:10.1002/adsc.200505473 Martin, R., & Buchwald, S. L. (2008). Palladium-Catalyzed Suzuki−Miyaura Cross-Coupling Reactions Employing Dialkylbiaryl Phosphine Ligands. Accounts of Chemical Research, 41(11), 1461-1473. doi:10.1021/ar800036s Wu, X.-F., Anbarasan, P., Neumann, H., & Beller, M. (2010). From Noble Metal to Nobel Prize: Palladium-Catalyzed Coupling Reactions as Key Methods in Organic Synthesis. Angewandte Chemie International Edition, 49(48), 9047-9050. doi:10.1002/anie.201006374 Li, G., & Jin, R. (2013). Catalysis by gold nanoparticles: carbon-carbon coupling reactions. Nanotechnology Reviews, 2(5), 529-545. doi:10.1515/ntrev-2013-0020 Corma, A., Juárez, R., Boronat, M., Sánchez, F., Iglesias, M., & García, H. (2011). Gold catalyzes the Sonogashira coupling reaction without the requirement of palladium ...

[EN] We show a facile method to prepare surface-clean monodispersed small and stable CuOx nanoparticles with controllable average sizes from below 1 nm up to similar to 5 nm without using bulk capping agent. Structural and surface characterizations show that the chemical states of CuOx nanoparticles and their interactions with O-2 are dependent on the particle size. To show their relevance to catalysis, the well-defined monodispersed CuOx nanoparticles have been used for oxidative coupling of alkynes. While the generally used CuCl catalysts presents a reaction induction period and agglomerate into CuOx nanoparticles during the reaction, the induction period disappears when monodispersed CuOx nanoparticles (similar to 2 nm) were used as catalyst. Supported CuOx nanoparticles on TiO2 behave in the same way as monodispersed CuOx nanoparticles. Kinetic, spectroscopic, and isotopic studies show that O-2 activation is the rate-controlling step and that the nature of the oxygen species formed on supported CuOx nanoparticles is dependent on the size of CuOx and determine the catalytic properties for oxidative coupling of alkynes. ; L.L. thanks ITQ for providing a contract. The authors also thank the Microscopy Service of UPV for kind help on TEM and STEM measurements. Financial supports from Consolider-Ingenio 2010 (project MULTICAT) and "Severo Ochoa" program are also gratefully acknowledged. The European Union is also acknowledged by ERC-AdG-2014-671093 - SynCatMatch. ; Liu, L.; Matsushita, T.; Concepción Heydorn, P.; Leyva Perez, A.; Corma Canós, A. (2016). Facile Synthesis of Surface-Clean Monodispersed CuOx Nanoparticles and Their Catalytic Properties for Oxidative Coupling of Alkynes. ACS Catalysis. 6(4):2211-2221. https://doi.org/10.1021/acscatal.5b02935 ; S ; 2211 ; 2221 ; 6 ; 4

[EN] Imines are ubiquitous intermediates in organic synthesis, and the metal-mediated imination of alcohols is one of the most direct and simple methods for their synthesis. However, reported protocols lack compatibility with many other functional groups since basic supports/media, pure oxygen atmospheres, and/or released hydrogen gas are required during reaction. Here we show that, in contrast to previous metal-catalyzed methods, hexa-aqueous Ru(III) catalyzes the imination of primary alcohols with very wide functional group tolerance, at slightly acid pH and under low oxygen atmospheres. The inorganic metal complex can be supported and stabilized, integrally, within either faujasite-type zeolites (Y and X) or a metal organic framework (MOF), to give a reusable heterogeneous catalyst which provides an industrially viable process well below the flammability limit of alcohols and amines. ; This work was supported by the MINECO (Spain) (Projects CTQ2017-86735-P, CTQ2016-75671-P, CTQ2014-56312-P, CTQ2014-55178-R, and MAT2013-40823-R and Excellence Units "Severo Ochoa" SEV2016-0683 and "Maria de Maeztu" and MDM-2015-0538) and the European Union through ERC-AdG-2014-671093 (SynCatMatch) and the Ministero dell'Istruzione, dell'Universita e della Ricerca (Italy) (FFABR 2017). M.M. thanks the MINECO for a predoctoral contract. RA. thanks UPV for a postdoctoral contract. J.F.-S. acknowledges financial support from the Subprograma Atraccio de Talent - Contractes Postdoctorals de la Universitat de Valencia. We also acknowledge SOLEIL for provision of the synchrotron radiation facility and thank Pierre Fertey for his assistance. ; Mon, M.; Adam-Ortiz, R.; Ferrando-Soria, J.; Corma Canós, A.; Pardo, E.; Armentano, D.; Leyva Perez, A. (2018). Stabilized Ru[(H2O)(6)](3+) in Confined Spaces (MOFs and Zeolites) Catalyzes the lmination of Primary Alcohols under Atmospheric Conditions with Wide Scope. ACS Catalysis. 8(11):10401-10406. https://doi.org/10.1021/acscatal.8b03228 ; S ; 10401 ; 10406 ; 8 ; 11

[EN] Propiolates cyclotrimerize in the presence of catalytic amounts of gold nanoparticles to give aryl benzoates in high yields and with turnover frequencies of thousands per hour. Types of alkynes other than propiolates do not react, and, if molecular oxygen is present and dissociated by the gold nanoparticles, electron-rich arenes engage with the propiolate to form a new C–C bond. The activation of propiolates and electron-rich arenes to form C–C bonds, beyond gold-catalyzed Michael additions, constitutes a new example of how and where gold nanoparticles modify the electronic density of unsaturated C–C bonds and opens the door to future transformations. ; A.L.-P. thanks CSIC for a contract. J.O.-M. thanks ITQ for a postgraduate scholarship. J.R.C.-A. and P.R.-M. thank MECD for the concession of a FPU contract. Financial support by the Severo Ochoa program and Consolider-Ingenio 2010 (proyecto MULTICAT) from MICIINN is acknowledged, and also the King Saud University. P.S. thanks European Union Seventh Framework programme (PIOF-GA-2009-253129). ; Leyva Perez, A.; Oliver Meseguer, J.; Cabrero Antonino, JR.; Rubio Marqués, P.; Serna, P.; Al-Resayes, SI.; Corma Canós, A. (2013). Reactivity of Electron-Deficient Alkynes on Gold Nanoparticles. ACS Catalysis. 3(8):1865-1873. https://doi.org/10.1021/cs400362c ; S ; 1865 ; 1873 ; 3 ; 8

[EN] Supramolecular coordination compounds (SCCs) represent the power of coordination chemistry methodologies to self-assemble discrete architectures with targeted properties. SCCs are generally synthesized in solution, with isolated fully coordinated metal atoms as structural nodes, thus severely limited as metal-based catalysts. Metal-organic frameworks (MOFs) show unique features to act as chemical nanoreactors for the in situ synthesis and stabilization of otherwise not accessible functional species. Here, we present the self-assembly of Pd-II SCCs within the confined space of a pre-formed MOF (SCCs@MOF) and its post-assembly metalation to give a Pd-II-Au-III supra molecular assembly, crystallography underpinned. These SCCs@MOFs catalyze the coupling of boronic acids and/or alkynes, representative multi-site metal-catalyzed reactions in which traditional SCCs tend to decompose, and retain their structural integrity as a consequence of the synergetic hybridization between SCCs and MOFs. These results open new avenues in both the synthesis of novel SCCs and their use in heterogeneous metal-based supramolecular catalysis. ; This work was supported by the MINECO (Spain) (Projects CTQ2016-75671-P and 2017-86735-P, and Excellence Units "Severn Ochoa" and "Maria de Maeztu" SEV-2016-0683 and MDM-2015-0538), the Ministero dell'Istruzione, dell'Universita e della Ricerca (Italy), and the Engineering and Physical Sciences Research Council (UK). M.M. thanks the MINECO for a predoctoral contract. RA. thanks UPV and R.G. thanks ITQ for the corresponding contracts. D.A. thanks the "Fondo per it finanziamento delle attivita base di ricerca". E.P. acknowledges financial support from the European Research Council under the European Union's Horizon 2020 research and innovation programme/ERC Grant Agreement No. 814804, MOF-reactors. Thanks are also extended to the "Subprograma Atraccio de Talent-Contractes Post-doctorals de la Universitat de Valencia" and the "2018 Leonardo Grant for Researchers and Cultural Creators, BBVA ...

[EN] Group 15 elements in zero oxidation state (P, As, Sb and Bi), also called pnictogens, are rarely used in catalysis due to the difficulties associated in preparing well-structured and stable materials. Here, we report on the synthesis of highly exfoliated, few layer 2D phosphorene and antimonene in zero oxidation state, suspended in an ionic liquid, with the native atoms ready to interact with external reagents while avoiding aerobic or aqueous decomposition pathways, and on their use as efficient catalysts for the alkylation of nucleophiles with esters. The few layer pnictogen material circumvents the extremely harsh reaction conditions associated to previous superacid-catalyzed alkylations, by enabling an alternative mechanism on surface, protected from the water and air by the ionic liquid. These 2D catalysts allow the alkylation of a variety of acid-sensitive organic molecules and giving synthetic relevancy to the use of simple esters as alkylating agents. ; We thank the European Research Council (ERC Starting Grant 804110 to G.A., and ERC Advanced Grant 742145 B-PhosphoChem to A.H.) for financial support. The research leading to these results was partially funded by the European Union Seventh Framework Program under grant agreement No. 604391 Graphene Flagship. G.A. has received financial support through the Postdoctoral Junior Leader Fellowship Program from "la Caixa" Banking Foundation (LCF/BQ/PI18/11630018). G.A. thanks support by the Deutsche Forschungsgemeinschaft (DFG; FLAG-ERA AB694/2-1), the Generalitat Valenciana (SEJI/2018/034 grant) and the FAU (Emerging Talents Initiative grant #WS16-17_Nat_04). Financial support by MINECO through the Excellence Unit Maria de Maeztu (MDM-2015-0538), Severo Ochoa (SEV-2016-0683) and RETOS (CTQ2014-55178-R) program is acknowledged. M.A.R.-C. thanks MINECO for the concession of a FPU fellowship. We also thank the DFG (DFG-SFB 953 "Synthetic Carbon Allotropes", Project A1), the Interdisciplinary Center for Molecular Materials (ICMM), and the Graduate School ...