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[EN] Novel aluminium MOF-type materials structured by 1D subdomains, such as organic-inorganic nanoribbons, were synthesized by modifying the conditions of solvothermal synthesis and the nature of the solvents in the presence of aryl monocarboxylate linkers with long alkyl chains, which acted as growth-modulating agents. Specifically, three different families of materials were prepared with various morphological characteristics: (i) isoreticular MIL-53(Al)-type materials, (ii) mesoscopic metalorganic structures and (iii) lamellar aluminium MOFs. The length of the alkyl chain in the aryl linker and the hydrophobic/hydrophilic nature of the solvothermal synthesis media determined the structuration level that was achieved. The derived Al-MOFs are active and stable catalysts for the synthesis of fine chemicals. This was illustrated by the efficient synthesis of 2,3-dihydro-2,2,4-trimethyl-1H-1,5-benzodiazepine. ; The authors are grateful for financial support from the Spanish Government under MAT2014-52085-C2-1-P, MAT2017-82288-C2-1-P and Severo Ochoa Excellence Program SEV-2016-0683. J. M. M. thanks predoctoral fellowships from MINECO for economic support. The European Union is also acknowledged for ERC-AdG-2014-671093-SynCatMatch ; Moreno, JM.; Velty, A.; Vidal Moya, JA.; Díaz Morales, UM.; Corma Canós, A. (2018). Growing modulator agents for the synthesis of Al-MOF-type materials based on assembled 1D structural sub-domains. Dalton Transactions. 47(15):5492-5502. https://doi.org/10.1039/C8DT00394G ; S ; 5492 ; 5502 ; 47 ; 15 ; Li, B., Wen, H.-M., Wang, H., Wu, H., Tyagi, M., Yildirim, T., … Chen, B. (2014). A Porous Metal–Organic Framework with Dynamic Pyrimidine Groups Exhibiting Record High Methane Storage Working Capacity. Journal of the American Chemical Society, 136(17), 6207-6210. doi:10.1021/ja501810r ; Getman, R. B., Bae, Y.-S., Wilmer, C. E., & Snurr, R. Q. (2011). Review and Analysis of Molecular Simulations of Methane, Hydrogen, and Acetylene Storage in Metal–Organic Frameworks. Chemical Reviews, ...

[EN] Controlling the location of acid sites in zeolites can have a great effect on catalysis. In this work we face the objective of directing the location of AI into the 10R channels of ZSM-5 by taking advantage of the structural preference of B to occupy certain positions at the channel intersections, as suggested by theoretical calculations. The synthesis of B-Al-ZSM-5 zeolites with variable Si/Al and Si/B ratios, followed by B removal in a postsynthesis treatment, produces ZSM-5 samples enriched in Al occupying positions at 10R channels. The location of the acid sites is determined on the basis of the product distribution of 1-hexene cracking as a test reaction. The higher selectivity to propene and lower C-4(=)/C-3(=) ratio in the samples synthesized with B and subsequently deboronated can be related to a larger concentration of acid sites in 10R channels, where monomolecular cracking occurs. Finally, several ZSM-5 samples have been tested in the methanol to propene reaction, and those synthesized through the B -assisted method show longer catalytic lifetime, higher propene yield, and lower yield of alkanes and aromatics. ; This work was supported by the European Union through ERC-AdG-2014-671093 (SynCatMatch) and the Spanish Government-MINECO through "Severo Ochoa" (SEV-2016-0683) and CTQ2015-70126-R. The Electron Microscopy Service of the UPV is acknowledged for their help in sample characterization. Red Espanola de Supercomputacion (RES) and Centre de Calcul de la Universitat de Valencia are gratefully acknowledged for computational resources and technical support. C.L. acknowledges the China Scholarship Council (CSC) for a Ph.D. fellowship ; Li, C.; Vidal Moya, JA.; Miguel, PJ.; Dedecek, J.; Boronat Zaragoza, M.; Corma Canós, A. (2018). Selective Introduction of Acid Sites in Different Confined Positions in ZSM-5 and Its Catalytic Implications. ACS Catalysis. 8(8):7688-7697. https://doi.org/10.1021/acscatal.8b02112 ; S ; 7688 ; 7697 ; 8 ; 8 ; Brand, H. V., Curtiss, L. A., & Iton, L. E. (1993). Ab ...

"This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS Catalysis, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/acscatal.9b04588" ; [EN] The catalysts used in the methanol-to-olefins (MTO) reaction are considered dual systems comprising an inorganic zeolite framework and organic compounds hosted inside that act as cocatalysts. The influence of zeolite cavity architecture on the preferential stabilization of cationic intermediates involved in the paring and side-chain routes of the hydrocarbon pool mechanism is analyzed by means of density functional theory (DFT) calculations, catalyst testing, and C-13 NMR spectroscopy for some small-pore cage-based zeolites. A correlation between the degree of methylation of the entrapped methylbenzenium (MB+) cations and the selectivity to ethene and propene is found experimentally and explained in terms of the electronic distribution of the first intermediate of the paring route. A deep understanding of the reaction mechanism and of the specific host guest interactions taking place inside zeolite catalysts allows establishing a quantitative parameter that is indicative for the contribution of the paring route and therefore the C-3(=)/C-2(=) ratio in the MTO reaction. ; This work has been supported by the European Union through ERC-AdG-2014-671093 (SynCatMatch), Spanish Government through "Severo Ochoa" (SEV-2016-0683, MINECO), MAT2017-82288-C2-1-P (AEI/FEDER, UE), and RTI2018-101033-B-100 (MCIU/AEI/FEDER, UE), and by the Fundacion Ramon Areces through a research contract (CIVP18A3908). The Electron Microscopy Service of the UPV is acknowledged for their help in sample characterization. Red Espanola de Supercomputacion (RES) and Servei d'Informatica de la Universitat de Valencia are acknowledged for computational resources and technical support. C.L. acknowledges the China Scholarship Council (CSC) for a ...

This is the peer reviewed version of the following article: Chem. Eur. J. 2019, 25, 16390 16396 , which has been published in final form at https://doi.org/10.1002/chem.201904043. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. ; [EN] Expanding the previously known family of -onium (ammonium, phosphonium, and sulfonium) organic structure-directing agents (OSDAs) for the synthesis of zeolite MFI, a new member, the arsonium cation, is used for the first time. The new group of tetraalkylarsonium cations has allowed the synthesis of the zeolite ZSM-5 with several different chemical compositions, opening a route for the synthesis of zeolites with a new series of OSDA. Moreover, the use of As replacing N in the OSDA allows the introduction of probe atoms that facilitate the study of these molecules by powder X-ray diffraction (PXRD), solid-state nuclear magnetic resonance (MAS NMR), and X-ray absorption spectroscopy (XAS). Finally, the influence of trivalent elements such as B, Al, or Ga isomorphically replacing Si atoms in the framework structure and its interaction with the As species has been studied. The suitability of the tetraalkylarsonium cation for carrying out the crystallization of zeolites is demonstrated along with the benefit of the presence of As atoms in the occluded OSDA, which allows its advanced characterization as well as the study of its evolution during OSDA removal by thermal treatments. ; Program Severo Ochoa SEV-2016-0683 and Maria de Maeztu MDM-2015-0538 are gratefully acknowledged. S.S-F. thanks MEC for his Severo Ochoa Grant SPV-2013-067884, P.O.-B. and G.M.E. thank MEC for his Ramon y Cajal contracts (RYC-2014-16620 and RYC-2013-14386). The authors thank the financial support by the Spanish Government (RTI2018-096399-A-I00, RTI2018-101784-B-I00 and CTQ2017-89528-P) and the Generalitat Valeciana (PROMETEO/2017/066). The Electron Microscopy Service of the UPV is acknowledged for their help in sample characterization. We ...

[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 ...