Minimal edge-transitive nets are regarded as suitable blueprints for the successful practice of reticular chemistry, and par excellence ideal for the deliberate design and rational construction of highly-coordinated metal-organic frameworks (MOFs). We report the systematic generation of the highly-connected minimal edge-transitive related nets (transitivity [32]) from parent edge-transitive nets (transitivity [21] or [11]), and their use as a guide for the deliberate design and directional assembly of highlycoordinated MOFs from their associated net-coded building units (net-cBUs), 12-connected (12-c) double six-membered ring (d6R) building units. Notably, the generated related nets enclose the distinctive highly-coordinated d6R (12-c) due to the subsequent coordination number increase in one node of the resultant new related net; that is, the (3,4,12)-c kce net is the (4,6)-c soc-related net, and the (3,6,12)-c kex and urx net are the (6,6)-c nia-related nets. Intuitively, the combination of 12-connected hexagonal prismatic rare-earth (RE) nonanuclear [RE9(μ3-O)2(μ3-OH)12(O2C−)12] carboxylate-based cluster, with purposely-chosen organic or organic-inorganic hybrid building units, led to the formation of the targeted highly-coordinated MOFs based on selected minimal edge-transitive related nets. Interestingly, the kex-MOFs can alternatively be regarded as a zeolite-like MOF (ZMOF) based on the zeolite underlying topology afx, by considering the dodecacarboxylate ligand as a d6R building unit, delineating a new avenue toward the construction of ZMOFs through the composite building units as net-cBUs. This represents a significant step toward the effective discovery and design of novel minimal edge-transitive and highly-coordinated materials using the d6Rs as net-cBUs. ASSOCIATED CONTENT Supporting InformationDetailed procedures for the synthesis of the organic ligands, PXRD, TGA, additional structural figures, adsorption isotherms, and single-crystal X-ray diffraction data (CIF). This material is available free of charge via the Internet at http://pubs.acs.org

We report here the first step by step anchoring of a W(≡C t Bu)(CH 2 t Bu) 3 complex on a highly crystalline and mesoporous MOF, namely Zr-NU-1000, using Surface organometallic Chemistry (SOMC) concept and methodology. SOMC allowed us to selectively graft the complex on the Zr 6 clusters and characterize the obtained single site material by using state of the art experimental methods including extensive solid-state NMR techniques and HAADF-STEM imaging. Further FT-IR spectroscopy revealed the presence of a W=O moiety arising from the in situ reaction of the W≡C t Bu functionality with the coordinated water coming from the 8-connected hexanuclear Zr 6 clusters. All the steps leading to the final grafted molecular complex have been identified by DFT. The obtained material was tested for gas phase and liquid phase olefin metathesis and exhibited higher catalytic activity than the corresponding catalysts synthesized by different grafting methods. This contribution establishes the importance of applying SOMC to MOF chemistry to get well defined single site catalyst on MOF inorganic secondary building units, in particular the in situ synthesis of W=O alkyl complexes from their W carbyne analogues.

Tungsten-hydrides supported on oxide supports are unique catalysts regarding the direct transformation of ethylene to propylene, alkane metathesis, and the low-temperature hydrogenolysis of waxes to lower molecular paraffins. The number of hydrides coordinated to the tungsten center and their structure on the siliceous support with very high surface silica (KCC-1) is unknown. KCC-1(700) silica of extremely high surface area allows for a high tungsten metal loading of 14 wt %. We show here the full characterization of supported tungsten bis- and tris-hydrides, which, after reaction with N2O gas, yield well-defined tungsten bis- and tris-hydroxide species on KCC-1(700). The obtained tungsten-hydroxide species are perfectly suitable for a detailed NMR study. The obtained tungsten hydroxo complexes are proven to be a tungsten bis-hydroxo and tungsten tris-hydroxo species. This analysis supports the conclusion that supported tungsten-hydride complexes coexist on the support as bis-hydride and tris-hydride species. They are, respectively, in close proximity to the silicon bis-hydride and the silicon mono-hydride. This proximity is explained by the mechanism of the formation of tungsten-hydride on the silica surface.

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