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[EN] In this work, a catalytic method is presented for the synthesis of aromatic carbamates from aromatic amines using dimethyl carbonate instead of phosgene as a green and safe reaction process. Microcrystalline Zr-MOF-808 is reported as an active and efficient heterogeneous catalyst for the selective carbamoylation of anilines and industrially relevant aromatic diamines, under mild reaction conditions with near quantitative yields. We have accomplished the selective growth of well-dispersed Zr-MOF-808 nanocrystals within the mesoporous material MCM-41. A superior catalytic performance of the Zr-MOF808@MCM-41 is demonstrated that together with increased stability stands out as an advantageous heterogeneous catalyst for polyurethane production. In situ FTIR studies have allowed a better understanding of the reaction pathway at the molecular level when the active MOF catalyst is present. ; This work was funded by the European Union through the European Research Council (grant ERC-AdG-2014-671093, SynCatMatch) and by the Spanish government through the Severo Ochoa program (SEV-2016-0683). S.R.-B. acknowledges a PhD fellowship from the Generalitat Valenciana. The Electron Microscopy Service of the Universitat Politecnica de Valenciais acknowledged for their help in sample characterization. ; Rojas-Buzo, S.; García-García, P.; Corma Canós, A. (2019). Zr-MOF-808@MCM-41 catalyzed phosgene-free synthesis of polyurethane precursors. Catalysis Science & Technology. 9(1):146-156. https://doi.org/10.1039/c8cy02235f ; S ; 146 ; 156 ; 9 ; 1 ; Tundo, P., & Selva, M. (2002). The Chemistry of Dimethyl Carbonate. Accounts of Chemical Research, 35(9), 706-716. doi:10.1021/ar010076f ; Fiorani, G., Perosa, A., & Selva, M. (2018). Dimethyl carbonate: a versatile reagent for a sustainable valorization of renewables. Green Chemistry, 20(2), 288-322. doi:10.1039/c7gc02118f ; Tundo, P., Rossi, L., & Loris, A. (2005). Dimethyl Carbonate as an Ambident Electrophile. The Journal of Organic Chemistry, 70(6), 2219-2224. ...

[EN] A chiral mesoporous organosilica material incorporating a urea based-cinchona derivative and propylamine groups was prepared by a co-condensation method. The multisite solid catalyst efficiently promoted the asymmetric multicomponent reaction of aldehydes, malonates and nitromethane. ; This work was supported by the Spanish Government (Consolider Ingenio 2010-MULTICAT (CSD2009-00050) and MAT2011-29020-C02-01). P.G.-G. is grateful for a JAE-DOC contract from CSIC co-funded by the ESF. The Severo Ochoa program is thankfully acknowledged. ; García García, P.; Zagdoun, A.; Coperet, C.; Lesage, A.; Díaz Morales, UM.; Corma Canós, A. (2013). In situ preparation of a multifunctional chiral hybrid organic-inorganic catalyst for asymmetric multicomponent reactions. Chemical Science. 4(5):2006-2012. https://doi.org/10.1039/C3SC22310H ; S ; 2006 ; 2012 ; 4 ; 5 ; José Climent, M., Corma, A., & Iborra, S. (2012). Homogeneous and heterogeneous catalysts for multicomponent reactions. RSC Adv., 2(1), 16-58. doi:10.1039/c1ra00807b ; Corma, A., Díaz, U., García, T., Sastre, G., & Velty, A. (2010). Multifunctional Hybrid Organic−Inorganic Catalytic Materials with a Hierarchical System of Well-Defined Micro- and Mesopores. Journal of the American Chemical Society, 132(42), 15011-15021. doi:10.1021/ja106272z ; Climent, M. J., Corma, A., & Iborra, S. (2011). Heterogeneous Catalysts for the One-Pot Synthesis of Chemicals and Fine Chemicals. Chemical Reviews, 111(2), 1072-1133. doi:10.1021/cr1002084 ; Ramón, D. J., & Yus, M. (2005). Asymmetric Multicomponent Reactions (AMCRs): The New Frontier. Angewandte Chemie International Edition, 44(11), 1602-1634. doi:10.1002/anie.200460548 ; Guillena, G., Ramón, D. J., & Yus, M. (2007). Organocatalytic enantioselective multicomponent reactions (OEMCRs). Tetrahedron: Asymmetry, 18(6), 693-700. doi:10.1016/j.tetasy.2007.03.002 ; Yu, J., Shi, F., & Gong, L.-Z. (2011). Brønsted-Acid-Catalyzed Asymmetric Multicomponent Reactions for the Facile Synthesis of Highly ...