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Metal-organic frameworks (MOFs) usually require meticulous removal of the solvent molecules to unlock their potential porosity. Herein, we report a novel one-step method for activating MOFs based on the photothermal effect induced by directly irradiating them with a UV-vis lamp. The localized light-to-heat conversion produced in the MOF crystals upon irradiation enables a very fast solvent removal, thereby significantly reducing the activation time to as low as 30 min and suppressing the need for time-consuming solvent-exchange procedures and vacuum conditions. This approach is successful for a broad range of MOFs, including HKUST-1, UiO-66-NH2, ZIF-67, CPO-27-M (M = Zn, Ni, and Mg), Fe-MIL-101-NH2, and IRMOF-3, all of which exhibit absorption bands in the light emission range. In addition, we anticipate that this photothermal activation can also be used to activate covalent organic frameworks (COFs). ; This work was supported by the Spanish MINECO (projects PN MAT2015-65354-C2-1-R), the Catalan AGAUR (project 2014 SGR 80), the ERC under the EU FP7 (ERC-Co 615954), and European Union's Horizon 2020 research and innovation programme under grant agreement No 685727. It was also funded by the CERCA Programme / Generalitat de Catalunya. ICN2 acknowledges the support of the Spanish MINECO through the Severo Ochoa Centers of Excellence Program, under Grant SEV2013-0295. J.E. acknowledges the MINECO for the FPI fellowship. ; Peer reviewed

The functionalization of an imine-based layered covalent organic framework (COF), containing phenanthroline units as ligands, has allowed the obtention of a heterobimetallated material. Photoactive Ir and Ni fragments were immobilized within the porous structure of the COF, enabling heterogeneous light-mediated Csp-Cspcross-couplings. As radical precursors, potassium benzyl- and alkoxy-trifluoroborates, organic silicates, and proline derivatives were employed, which brings out the good versatility ofIr,Ni@Phen-COF. Moreover, in all the studied cases, an enhanced activity and stability have been observed in comparison with analogous homogenous systems. ; Financial support was provided by the European Research Council (ERC-CoG, contract no. 647550), the Spanish Government (RTI2018-095038-B-I00, PID2019-110637RB-I00), "Comunidad de Madrid", and European Structural Funds (S2018/NMT-4367). A.L.M. thanks to UAM for FPI-UAM predoctoral fellowship. ICN2 is supported by the Severo Ochoa programme from the Spanish MINECO (Grant No. SEV-2017-0706).

The functionalization of an imine-based layered covalent organic framework (COF), containing phenanthroline units as ligands, has allowed the obtention of a heterobimetallated material. Photoactive Ir and Ni fragments were immobilized within the porous structure of the COF, enabling heterogeneous light-mediated Csp3-Csp2cross-couplings. As radical precursors, potassium benzyl- and alkoxy-trifluoroborates, organic silicates, and proline derivatives were employed, which brings out the good versatility ofIr,Ni@Phen-COF. Moreover, in all the studied cases, an enhanced activity and stability have been observed in comparison with analogous homogenous systems ; Financial support was provided by the European Research Council (ERC-CoG, contract no. 647550), the Spanish Government (RTI2018-095038-B-I00, PID2019-110637RB I00), "Comunidad de Madrid", and European Structural Funds (S2018/NMT-4367). A.L.M. thanks to UAM for FPI-UAM predoctoral fellowship. ICN2 is supported by the Severo Ochoa programme from the Spanish MINECO (Grant No. SEV-2017-0706)

arXiv:1509.07291v1 ; We report characterization and magnetic studies of mixtures of micrometer-size ribbons of Mn12 acetate and micrometer-size particles of YBaCuO superconductor. Extremely narrow zero-field spin-tunneling resonance has been observed in the mixtures, pointing to the absence of the inhomogeneous dipolar broadening. It is attributed to the screening of the internal magnetic fields in the magnetic particles by Meissner currents flowing between superconducting grains surrounding the particles. ; The work at the University of Barcelona has been supported by the Spanish Government Project No. MAT2011-23698. A.G.-S. acknowledges support from Universitat de Barcelona. I.I. and J.E. thank the MINECO for the Ramon y Cajal contract and the FPI fellowship, respectively. The work of EMC at CUNY Lehman College has been supported by the Office of Science of the U.S. Department of Energy through grant No. DE-FG02-93ER45487. ; Peer reviewed

Under the terms of the Creative Commons Attribution license (3.0 Unported or 4.0 International).-- et al. ; We report measurements and theoretical analysis of resonant spin tunneling in randomly oriented nanospheres of a molecular magnet. Amorphous nanospheres of Mn 12 acetate have been fabricated and characterized by chemical, infrared, TEM, x-ray, and magnetic methods. Magnetic measurements have revealed sharp tunneling peaks in the field derivative of the magnetization that occur at the typical resonant field values for the Mn 12 acetate crystal in the field parallel to the easy axis. Theoretical analysis is provided that explains these observations. We argue that resonant spin tunneling in a molecular magnet can be established in a powder sample, without the need for a single crystal and without aligning the easy magnetization axes of the molecules. This is confirmed by reanalyzing the old data on a powdered sample of nonoriented micron-size crystals of Mn 12 acetate. Our findings can greatly simplify the selection of candidates for quantum spin tunneling among newly synthesized molecular magnets. ; The work at the University of Barcelona has been supported by Spanish Government Project No. MAT2011-23698. S.L. acknowledges financial support from the FPU Program of Ministerio de Educacion, Cultura, y Deporte of the Spanish Government. I.I. and J.E. thank the MINECO for the Ramon y Cajal contract and the FPI fellowship, respectively. The work of E.M.C. at Lehman College is supported by the US National Science Foundation through Grant No. DMR-1161571. S.J.L.B. was supported by DOE-BES under Contract No. DE-AC02-98CH10886. ; Peer reviewed

Tandem and multicomponent one‐pot reactions are highly attractive because they enable synthesis of target molecules in a single reaction vessel. However, they are difficult to control, as they can lead to the formation of many undesired side‐products. Herein we report the use of metal‐organic framework (MOF) pores decorated with organocatalytic squaramide moieties to confine ring‐opening epoxide reactions of diverse substrates. Controlled mono‐addition or tandem reactions inside the pores yield 1,2‐aminoalcohols or 1,2,2′‐aminodialcohols, respectively, in good yields. In addition, this squaramide‐functionalised MOF enables catalysis of higher‐complexity multicomponent reactions such as the catalytic ring‐opening of two different epoxides by a single amine to afford 1,2,2′‐aminodialcohols. ; This work was supported by the Spanish MINECO (projects PN MAT2015‐65354‐C2‐1‐R and CTQ2015‐64561‐R), the Catalan AGAUR (project 2014 SGR 80), the ERC under the EU FP7 (ERC−Co 615954 and ERC‐CG 647550), and European Union's Horizon 2020 research and innovation programme under grant agreement No 685727. It was also funded by the CERCA Programme/Generalitat de Catalunya. ICN2 acknowledges the support of the Spanish MINECO through the Severo Ochoa Centers of Excellence Program, under Grant SEV‐2013‐0295. ; Peer reviewed

This is the peer reviewed version of the following article: ChemCatChem 10 (2018): 3995-3998, which has been published in final form at http://doi.org/10.1002/cctc.201801127. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions ; Tandem and multicomponent one-pot reactions are highly attractive because they enable synthesis of target molecules in a single reaction vessel. However, they are difficult to control, as they can lead to the formation of many undesired side-products. Herein we report the use of metal-organic framework (MOF) pores decorated with organocatalytic squaramide moieties to confine ring-opening epoxide reactions of diverse substrates. Controlled mono-addition or tandem reactions inside the pores yield 1,2-aminoalcohols or 1,2,2′-aminodialcohols, respectively, in good yields. In addition, this squaramide-functionalised MOF enables catalysis of higher-complexity multicomponent reactions such as the catalytic ring-opening of two different epoxides by a single amine to afford 1,2,2′-aminodialcohols ; This work was supported by the Spanish MINECO (projects PNMAT2015-65354-C2-1-R and CTQ2015-64561-R), the CatalanAGAUR (project 2014 SGR 80), the ERC under the EU FP7 (ERCCo615954 and ERC-CG 647550), and European Union's Horizon 2020research and innovation programme under grant agreementNo 685727. It was also funded by the CERCA Programme/General-itat de Catalunya

Here, we report the design, synthesis, and functional testing of enzyme-powered porous micromotors built from a metal–organic framework (MOF). We began by subjecting a presynthesized microporous UiO-type MOF to ozonolysis, to confer it with mesopores sufficiently large to adsorb and host the enzyme catalase (size: 6–10 nm). We then encapsulated catalase inside the mesopores, observing that they are hosted in those mesopores located at the subsurface of the MOF crystals. In the presence of H2O2 fuel, MOF motors (or MOFtors) exhibit jet-like propulsion enabled by enzymatic generation of oxygen bubbles. Moreover, thanks to their hierarchical pore system, the MOFtors retain sufficient free space for adsorption of additional targeted species, which we validated by testing a MOFtor for removal of rhodamine B during self-propulsion. ; This work was supported by BIST-IGNITE (MOFtors), the Spanish MINECO (project RTI2018-095622-B-I00), the Catalan AGAUR (project 2017 SGR 238), and the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement No 866348: iNanoSwarms). It was also funded by the CERCA Program/Generalitat de Catalunya. ICN2 is supported by the Severo Ochoa program from the Spanish MINECO (Grant No. SEV-2017-0706). Y.Y. acknowledges the China Scholarship Council for scholarship support. X.A. thanks the Spanish MINECO for the Severo Ochoa program (SEV-2014-0425) for the PhD fellowship (PRE2018-083712).

Título del post-print: Rational design of heterogeneous catalysts with programmable topologies by reticulation of organocatalysts into metal-organic frameworks: the case of squaramide ; A well-established strategy to synthesize heterogeneous, metal-organic framework (MOF) catalysts that exhibit nanoconfinement effects, and specific pores with highly-localized catalytic sites, is to use organic linkers containing organocatalytic centers. Here, we report that by combining this linker approach with reticular chemistry, and exploiting three-dimensioanl (3D) MOF-structural data from the Cambridge Structural Database, we have designed four heterogeneous MOF-based catalysts for standard organic transformations. These programmable MOFs are isoreticular versions of pcu IRMOF-16, fcu UiO-68 and pillared-pcu SNU-8X, the three most common topologies of MOFs built from the organic linker p,p'-terphenyldicarboxylic acid (tpdc). To synthesize the four squaramide-based MOFs, we designed and synthesized a linker, 4,4'-((3,4‐dioxocyclobut‐1‐ene‐1,2‐diyl)bis(azanedyil))dibenzoic acid (Sq_tpdc), which is identical in directionality and length to tpdc but which contains organocatalytic squaramide centers. Squaramides were chosen because their immobilization into a framework enhances its reactivity and stability while avoiding any self-quenching phenomena. Therefore, the four MOFs share the same organocatalytic squaramide moiety, but confine it within distinct pore environments. We then evaluated these MOFs as heterogeneous H-bonding catalysts in organic transformations: a Friedel-Crafts alkylation and an epoxide ring-opening. Some of them exhibited good performance in both reactions but all showed distinct catalytic profiles that reflect their structural differences ; This work was supported by the Spanish MINECO (projects RTI2018-095622-B-I00 and RTI2018-095038-B-I00), the Catalan AGAUR (project 2017 SGR 238), the ERC under the EU FP7 (ERC−Co 615954), European Union's Horizon 2020 research and innovation program under grant agreement No. 685727, and European Structural Funds (S2018/NMT-4367). It was also funded by the CERCA Program/Generalitat de Catalunya. ICN2 is supported by the Severo Ochoa program from the Spanish MINECO (Grant No. SEV-2017-0706)

This document is the Accepted Manuscript version of a Published Work that appeared in final form in Journal of the American Chemical Society, 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/jacs.9b12389 ; Covalent organic frameworks (COFs) are commonly synthesized under harsh conditions yielding unprocessable powders. Control in their crystallization process and growth has been limited to studies conducted in hazardous organic solvents. Herein, we report a one-pot synthetic method that yields stable aqueous colloidal solutions of sub-20 nm crystalline imine-based COF particles at room temperature and ambient pressure. Additionally, through the combination of experimental and computational studies, we investigated the mechanisms and forces underlying the formation of such imine-based COF colloids in water. Further, we show that our method can be used to process the colloidal solution into 2D and 3D COF shapes as well as to generate a COF ink that can be directly printed onto surfaces. These findings should open new vistas in COF chemistry, enabling new application areas ; This work was supported by the European Union (ERC-2015-STG microCrysFact 677020), the Swiss National Science Foundation (Project No. 200021_181988), ETH Zürich and Ministry of Science, Innovation and Universities MICINN (MAT2016-77608-C3-1P). R.P. acknowledges the Spanish MINECO (Grant No. CTQ2017—88948-P). A.E.P.P. acknowledges a TALENTO grant (2017-T1/IND5148) from Comunidad de Madrid. I.S. acknowledges the Ministry of Human Capacities of Hungary (20391-/2018/FEKUSTRAT). G.M.P. acknowledges the funding received by the Swiss National Science Foundation (SNSF grant number 200021_175735) and by the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement No. 818776 - DYNAPOL). D.M. acknowledges financial support from the European Union (ERC-Co 615954). ICN2 is supported by the Severo Ochoa program from the Spanish MINECO (Grant No. SEV-2017-0706). S.P. acknowledges funding from a Consolidator Grant from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (Grant Agreement No. 771565). We acknowledge DESY (Hamburg, Germany), a member of the Helmholtz Association HGF, for the provision of experimental facilities. Synchrotron X-ray diffraction experiments with COF-TAPB-BTCA were carried out at the beamline P02.1 PETRA III under the proposal I-20170717 EC. We acknowledge Jaume Caelles for SAXS/WAXS measurements performed at IQAC–CSIC.

Covalent organic frameworks (COFs) are commonly synthesized under harsh conditions yielding unprocessable powders. Control in their crystallization process and growth has been limited to studies conducted in hazardous organic solvents. Herein, we report a one-pot synthetic method that yields stable aqueous colloidal solutions of sub-20 nm crystalline imine-based COF particles at room temperature and ambient pressure. Additionally, through the combination of experimental and computational studies, we investigated the mechanisms and forces underlying the formation of such imine-based COF colloids in water. Further, we show that our method can be used to process the colloidal solution into 2D and 3D COF shapes as well as to generate a COF ink that can be directly printed onto surfaces. These findings should open new vistas in COF chemistry, enabling new application areas. ; This work was supported by the European Union (ERC-2015-STG microCrysFact 677020), the Swiss National Science Foundation (Project No. 200021_181988), ETH Zürich and Ministry of Science, Innovation and Universities MICINN (MAT2016-77608-C3-1P). R.P. acknowledges the Spanish MINECO (Grant No. CTQ2017—88948-P). A.E.P.P. acknowledges a TALENTO grant (2017-T1/IND5148) from Comunidad de Madrid. I.S. acknowledges the Ministry of Human Capacities of Hungary (20391-/2018/FEKUSTRAT). G.M.P. acknowledges the funding received by the Swiss National Science Foundation (SNSF grant number 200021_175735) and by the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement No. 818776 - DYNAPOL). D.M. acknowledges financial support from the European Union (ERC-Co 615954). ICN2 is supported by the Severo Ochoa program from the Spanish MINECO (Grant No. SEV-2017-0706). S.P. acknowledges funding from a Consolidator Grant from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (Grant Agreement No. 771565). We acknowledge DESY (Hamburg, Germany), a member of the Helmholtz Association HGF, for the provision of experimental facilities. Synchrotron X-ray diffraction experiments with COF-TAPB-BTCA were carried out at the beamline P02.1 PETRA III under the proposal I-20170717 EC. We acknowledge Jaume Caelles for SAXS/WAXS measurements performed at IQAC–CSIC. ; Peer reviewed