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This work describes a facile approach to modify metal-organic frameworks (MOFs) with ionic liquids (ILs), rendering them as useful heterogeneous catalysts for CO chemical fixation. An amino-functionalized imidazolium-based ionic liquid is firmly grafted into the porous MOF, MIL-101-SOH by the acid-base attraction between positively charged ammonium groups on the IL and negatively charged sulfonate groups from the MOF. Analyses by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, H NMR, and N sorption experiments reveal the MOF-supported ionic liquid (denoted as IL@MOF) material remains intact while functioning as a recyclable heterogeneous catalyst that can efficiently convert CO and epichlorohydrin into chloropropene carbonate without the addition of a cocatalyst.

This review article summarizes the recent progress in the pore surface engineering of covalent organic frameworks (COFs) for various applications.

Chemical functionalization or docking of transition-metal ions in covalent organic frameworks (COFs) is of importance for calibrating properties and widening potential applications. In this work, we demonstrate the successful decoration of COF with vanadium as exemplified in the context of post-synthetically modifying two-dimensional COF that features eclipsed stacking structure, large pores, hydroxyl functionalities, high thermal and chemical stability using vanadyl acetylacetonate. The potent catalytic behavior of vanadiumdecorated COF was systematically investigated in the reactions of Prins condensation and sulfide oxidation, which revealed its excellent catalytic performances in terms of efficacious activity, preservation of framework crystallinity and reusability. Our work not only contributes the first ever report of vanadium-decorated COF-catalyzed Prins reaction and sulfide oxidation but paves a new way for docking COF with metals for a broad range of applications.

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Thec atalytic nature of self-assembled metal-organic polyhedra gives an entirely new dimension to the reactivity andproperties of molecules within aw ell-defined confined space. Encapsulation of ar ange of guests brings about not only host-guest interactions but also gives riset ou nusual reactivities with selectivity ands tabilizationo fv arious reactive intermediates.T his review briefly covers the synthesis of self-assembled metal-organic polyhedra and elaborates theiri nfluence in different chemical reactions as well as in the stabilization of unstablechemical species. 1I ntroduction 2S elf-Assembled Metal-Organic Polyhedra 3C atalysis 4S tabilization of Reactive Species 5C onclusions and PerspectiveKeywords: catalysts;h ost-guest systems;m etal-organic polyhedra;n on-covalent interactions;s elf-assembly 1I ntroduction "Chemistry without catalysis would be asword without ah andle,alight without brilliance,abell without sound." Alwin MittaschSelf-assembly is defined by George Whitesides as "a process where predesigned components assembled in ad etermined structure without the intervention of human operators". [1] It is an effectivetooltoc onstruct various supramoleculesh aving different shapesa nd functionalitiesd irectly from the precursor units.T he recognition of non-covalent interactions such as ionion, ion-dipole, p-p stacking, hydrogenb onding, etc. can be correlated to the invention of "crown ethers", "cryptands" and" spherands" by Pedersen, [2] Lehn, [3] and Cram, [4] respectively.M etal-organic polyhedra, zero-dimensional discrete structures usuallyp repared by the self-assembly of metal ions andh ighly directional m-BDC or bispyridine or exo-/endo-functionalized ligands possessings uitable symmetrical axesa nd point groups.T hese discrete structures can be categorized as platonic, archimedean, faceted and stellated possessing an internal cavity for the encapsulation of various species,m oreover, the nature and volume of the cavity are two of the importantp arameters for altering the chemical reactivity andd ynamics of substrates. [5] Thec atalytic nature of the polyhedra can be correlated to enzyme catalysis, [6] where preorganization and non-covalent interactions are of the utmost importance.T hese non-covalent interactions between the host and guest provide an extra stability to the intermediates and decide the fate of ar eaction.Additionally,t he cavity also serves as an acceptable destination for range of unstable species including greenhouse gases, whitep hosphorus,o rganometallic reagents.T his meddling of polyhedra is basicallyd ue to its structural constraints and chemical/thermal stability in acidic, basic or various solvents.I nt his brief review,w ew illd iscuss the synthesis of few important polyhedra and highlight theird irect or indirecti nfluence on substrate reactivity and in stabilizing reactive species.

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An In(III) based metal−organic framework (MOF), In-pbpta, with soc topology was constructed from the trigonal prismatic [In 3 (μ 3 -O)(H 2 O) 3 (O 2 C−) 6 ] secondary building unit (SBU) and a custom-designed tetratopic linker H 4 pbpta (pbpta = 4,4′,4″,4‴-(1,4-phenylenbis(pyridine-4,2,6-triyl))-tetrabenzoic acid)). The obtained MOF shows a Brunauer−Emmett− Teller surface area of 1341 m 2 /g with a pore volume of 0.64 cm 3 /g, which is the highest among the scarcely reported In-soc-MOFs. The constructed MOF demonstrates excellent performance as a heterogeneous Lewis acid catalyst for highly efficient conversion in a one-pot multicomponent Strecker reaction for the preparation of α-aminonitriles under solvent-free conditions, which can be easy to separate and recycle without significant loss of activity for up to seven cycles. The computational modeling studies suggest the presence of the three substrates in close vicinity to the In-oxo cluster. The strong interactions of the aldehyde/ketone and the amine with the In-oxo cluster together with the readily available cyanide ion around the In-oxo cluster lead to high catalytic conversion within a short period of time for the MOF catalyst. Our work therefore lays a foundation to develop MOF as a new class of efficient heterogeneous catalyst for one-pot Strecker reaction.