The combination of well-defined molecular cavities and chemical functionality makes crystalline porous solids attractive for a great number of technological applications, from catalysis to gas separation. However, in contrast to other widely applied synthetic solids such as polymers, the lack of processability of crystalline extended solids hampers their application. In this work, we demonstrate that highly crystalline porous solids, metal-organic frameworks, can be made solution processable via outer surface functionalization using N-heterocyclic carbene ligands. Selective outer surface functionalization of relatively large nanoparticles (250 nm) of the well-known metal organic framework ZIF-67 allows for the stabilization of processable dispersions exhibiting permanent porosity. The resulting type III porous liquids can either be directly deployed as liquid adsorbents or be co-processed with state-of-the-art polymers to yield highly loaded mixed matrix membranes with excellent mechanical properties and an outstanding performance in the challenging separation of propylene from propane. We anticipate that this approach can be extended to other metal-organic frameworks, and for other applications.

SiO in a complex: The first silanone that is stable at room temperature (3) is reported. The two-step synthesis involves carbonylation of the silylidyne complex 1 to give the chromiosilylene 2, followed by oxidation of 2 with N2 O. Silanone 3 features a polar, short SiO bond (1.526(3) Å) to a trigonal-planar-coordinated silicon center and reacts with water to give the dihydroxysilyl complex.

Si 2+ ions are highly reactive, two-valence-electron species that have been generated in laser-induced plasmas and studied by photoabsorption and microwave spectroscopy. [1] The ions have also been employed as implants for waveguide fabrication in lithium niobate crystals, which are of great interest for various photonic applications owing to their physical and electro-optical properties. [2] A possible method of trapping these highly electrophilic ions in the condensed phase, may involve complexation by three strongly basic, neutral ligands (L) to give dications of the general formula [SiL 3 ] 2+ , in which the silicon center attains a noble gas configuration. However, dicationic silicon(II) complexes are presently unknown, in marked contrast to the few germanium homologues, which were reported some years ago by K. M. Baines et al. [3] This difference can be explained by the anomalous low electronegativity of silicon versus germanium, [4] which makes the isolation of silicon(II)-centered dications a highly challenging goal. Even monocationic silicon(II) compounds are very rare, and only the nido-type cluster cation [(C 5 Me 5 )Si] + , [5] [6] and the Si II cation [{C 10 H 6a,a-NP(nBu) 3 }SiCl] + stabilized by a chelating bis(iminophosphorane) ligand [7] have been isolated thus far.Since the first report of the silicon(0) compound [Si 2 -(Idipp) 2 ] (Idipp = 1,3-bis(2,6-diisopropylphenyl)-imidazol-2ylidene) by G. Robinson et al. in 2008, [8] N-heterocyclic carbenes have been shown to be particularly effective ligands for the stabilization of silicon compounds in unusually low oxidation states. Remarkable examples include NHC adducts of the dihalosilylenes SiX 2 (X = Cl, Br), [9] which are very valuable precursors in Si II chemistry, [9c, 10] or NHC adducts of the organohalosilylenes RSiCl (R = m-terphenyl, (2,6-diisopropylphenyl)(trimethylsilyl)amino), [11] which paved the way for the preparation of the first complexes featuring metalsilicon triple bonds. [12] Herein, the exchange of NHC ligands at Si II centers is illustrated for the first time to provide access to unprecedented dicationic NHC complexes of silicon(II) and NHC adducts of the iodosilyliumylidene cation SiI + .The entry into this chemistry started with the triiodosilylimidazolium salt 1 (Scheme 1), which was obtained from the reaction of SiI 4 with Idipp in toluene and isolated as a yellow, thermally robust solid in 96 % yield. Reduction of 1 with potassium graphite (2.3 equiv) in benzene afforded the yellow NHC-diiodosilylene adduct 2-I in 81 % yield (Scheme 1). [13] Under rigorous exclusion of air, the silicon(II) compound 2-I is stable in benzene or toluene solution at ambient temperature for several days, and decomposes in the solid state upon heating above 160 8C.The solid-state structure of 1·3 (CHCl 3 ) was determined by single-crystal X-ray crystallography. [13] It resembles that of [SiBr 3 (Idipp)]Br·3 (CH 2 Cl 2 ) [9b] and reveals that the chloroform trissolvate of 1 is composed of well separated [SiI 3 -(Idipp)] + cations and i...

The first base-metal-catalysed hydrogenation of CO -derived carbonates to alcohols is presented. The reaction proceeds under mild conditions in the presence of a well-defined manganese complex with a loading as low as 0.25 mol %. The non-precious-metal homogenous catalytic system provides an indirect route for the conversion of CO into methanol with the co-production of value-added (vicinal) diols in yields of up to 99 %. Experimental and computational studies indicate a metal-ligand cooperative catalysis mechanism.

A protocol for the fast and selective two-electron reduction of the potent greenhouse gas sulfur hexafluoride (SF6) by organic electron donors at ambient temperature has been developed.