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Palladacyclic architectures have been shown as versatile motifs in cross-coupling reactions. NHC-ligated palladacycles possessing unique electronic and steric properties have helped to stabilize the catalytically active species and provide additional control over reaction selectivity. Here, we report on a synthetic protocol leading to palladacycle complexes using a mild base and an environmentally desirable solvent, with a focus on complexes bearing backbone-substituted N-heterocyclic carbene ligands. The readily accessible complexes exhibit high catalytic activity in the Buchwald–Hartwig amination. This is achieved using low catalyst loading and mild reaction conditions in a green solvent. [ABSTRACT FROM AUTHOR]

A straightforward synthetic protocol leading to carbene–metal–amido (CMA) complexes (metal=Au, Cu) using a mild base and an environmentally desirable solvent (EtOH) has been explored, with a focus on complexes bearing backbone‐substituted N‐heterocyclic carbene (NHC) ligands, including BIAN‐NHCs (BIAN=bis(imino)acenaphthene). The novel CMAs were structurally characterized, and gold‐based CMAs bearing diverse NHCs were screened as simple, Brønsted‐basic precatalysts. The readily accessible complexes display high catalytic activity in the intermolecular and intramolecular hydrocarboxylation of internal alkynes and alkynoic acids respectively, while the screening reveals the ancillary ligand effect of NHCs in these catalytic systems. [ABSTRACT FROM AUTHOR]

Gold catalysis has witnessed immense evolution in recent years, yet it still requires the use of activators to render the common [AuCl(L)] complexes catalytically active. Herein, the H-bonding donor properties of hexafluoroisopropanol (HFIP) are utilized for Au–Cl bond activation and the ancillary ligand and counteranion effects on cycloisomerization reactions are showcased in HFIP as solvent. [ABSTRACT FROM AUTHOR]

The use of weak and inexpensive bases has recently opened promising perspectives towards the simpler and more sustainable synthesis of Au(I)‐aryl complexes with valuable applications in catalysis, medicinal chemistry, and materials science. In recent years, continuous manufacturing has shown to be a reliable partner in establishing sustainable and controlled process scalability. Herein, the first continuous flow synthesis of a range of Au(I)‐aryl starting from widely available boronic acids and various [Au(NHC)Cl] (NHC=N‐heterocyclic carbene) complexes in unprecedentedly short reaction times and high yields is reported. Successful synthesis of previously non‐ or poorly accessible complexes exposed fascinating reactivity patterns. Via a gram‐scale synthesis, convenient process scalability of the developed protocol was showcased. [ABSTRACT FROM AUTHOR]

Secondary ligand–metal interactions are decisive in many catalytic transformations. While arene–gold interactions have repeatedly been reported as critical structural feature in many high‐performance gold catalysts, we herein report that these interactions can also be replaced by Au⋅⋅⋅H−C hydrogen bonds without suffering any reduction in catalytic performance. Systematic experimental and computational studies on a series of ylide‐substituted phosphines featuring either a PPh3 (PhYPhos) or PCy3 (CyYPhos) moiety showed that the arene‐gold interaction in the aryl‐substituted compounds is efficiently compensated by the formation of Au⋅⋅⋅H−C hydrogen bonds. The strongest interaction is found with the C−H moiety next to the onium center, which due to the polarization results in remarkably strong interactions with the shortest Au⋅⋅⋅H−C hydrogen bonds reported to date. Calorimetric studies on the formation of the gold complexes further confirmed that the PhYPhos and CyYPhos ligands form similarly stable complexes. Consequently, both ligands showed the same catalytic performance in the hydroamination, hydrophenoxylation and hydrocarboxylation of alkynes, thus demonstrating that Au⋅⋅⋅H−C hydrogen bonds are equally suited for the generation of highly effective gold catalysts than gold‐arene interactions. The generality of this observation was confirmed by a comparative study between a biaryl phosphine ligand and its cyclohexyl‐substituted derivative, which again showed identical catalytic performance. These observations clearly support Au⋅⋅⋅H−C hydrogen bonds as fundamental secondary interactions in gold catalysts, thus further increasing the number of design elements that can be used for future catalyst construction. [ABSTRACT FROM AUTHOR]

A simple and efficient synthetic route to [RuCl2(NHC)(p-cymene)] and [Ru(CO3)(NHC)(p-cymene)] complexes making use of a weak base, under aerobic conditions, is reported. This method enables access to a series of NHC-ruthenium compounds with moderate to good yields under mild conditions. The Ru pre-catalysts were successfully used in olefin oxidation catalysis at low catalyst loading and reach complete conversion in short times. [ABSTRACT FROM AUTHOR]

A general, user-friendly synthetic route to [Pt(NHC)(L)Cl2] and [Pt(NHC)(dvtms)] (L = DMS, Py; DMS = dimethyl sulfide, dvtms = divinyltetramethylsiloxane, Py = pyridine) complexes has been developed. The procedure is applicable to a wide range of ligands and enables facile synthetic access to key Pt(0)- and Pt(II)-NHC complexes used in hydrosilylation catalysis. [ABSTRACT FROM AUTHOR]

Covalent triazine frameworks (CTFs) have provided a unique platform in functional material design for a wide range of applications. This work reports a series of new CTFs with two new heteroaromatic building blocks (pyrazole and isoxazole groups) through a building‐block transformation approach aiming for carbon capture and storage (CCS) and metal‐free catalysis. The CTFs were synthesized from their respective building blocks [(4,4′‐(1H‐pyrazole‐3,5‐diyl)dibenzonitrile (pyz) and 4,4′‐(isoxazole‐3,5‐diyl)dibenzonitrile (isox))] under ionothermal conditions using ZnCl2. Both of the building blocks were designed by an organic transformation of an acetylacetone containing dinitrile linker to pyrazole and isoxazole groups, respectively. Due to this organic transformation, (i) linker aromatization, (ii) higher surface areas and nitrogen contents, (iii) higher aromaticity, and (iv) higher surface basicity was achieved. Due to these enhanced properties, CTFs were explored for CO2 uptake and metal‐free heterogeneous catalysis. Among all, the isox‐CTF, synthesized at 400 °C, showed the highest CO2 uptake (4.92 mmol g−1 at 273 K and 2.98 mmol g−1 at 298 K at 1 bar). Remarkably, these CTFs showed excellent metal‐free catalytic activity for the aerobic oxidation of benzylamine at mild reaction conditions. On studying the properties of the CTFs, it was observed that organic transformations and ligand aromatization of the materials are crucial factor to tune the important parameters that influence the CO2 uptake and the catalytic activity. Overall, this work highlights the substantial effect of designing new CTF materials by building‐block organic transformations resulting in better properties for CCS applications and heterogeneous catalysis. [ABSTRACT FROM AUTHOR]

Two Co(II) coordination polymers, formulated as [Co(bix)(tbta)] n ( 1 ) and [Co(bix) 0.5 (aip)(H 2 O)] n ( 2 ) (bix = 1,4-bis(imidazol-1-ylmethyl)benzene, H 2 tbta = tetrabromoterephthalic acid, H 2 aip = 5-aminoisophthalic acid) have been synthesized and structurally characterized by single crystal X-ray diffraction. Complex 1 features a 3D three-fold interpenetrating diamond framework. Complex 2 is a 2D (3,4) network with 3,4L83 topology and extend into an unusual (5,6)-connected 3D supramolecular framework via intermolecular hydrogen bonds. In addition, fluorescence and catalytic performances of complexes 1 and 2 for the degradation of Congo red dye in a photo-Fenton-like process were investigated. [ABSTRACT FROM AUTHOR]

Three metal-organic coordination polymers, namely {[Cd(L1)(1,2-chdc)] ·2H2O} n ( 1), {[Ni(L2)(1,2-chdc)] ·H2O} n ( 2), and [Cd(L2)(npht)] n ( 3) [L1 = 1,2-bis(2-methylbenzimidazol-1-ylmethyl)benzene, L2 = 1,2-bis(5,6-dimethylbenzimidazol-1-ylmethyl)benzene, 1,2-H2chdc = 1,2-cyclohexanedicarboxylic acid, H2npht = 3-nitrophthalic acid] were synthesized under hydrothermal conditions and structurally characterized by single-crystal X-ray diffraction methods, IR spectroscopy, TGA, and elemental analysis. In compound 1, two 1,2-chdc2- ligands connect two neighboring Cd atoms to form a dinuclear [Cd2(1,2-chdc)2] subunit, which is further linked by L1 ligands to construct a 1D ladder-like chain. Compound 2 exhibits a 2D (4,4) coordination network with {44.62} topology, whilst compound 3 shows a 1D helical chain structure. The fluorescence, UV/Vis diffuse reflection spectra, and catalytic properties of complexes 1- 3 for the degradation of the congo red azo dye in a Fenton-like process are investigated. [ABSTRACT FROM AUTHOR]

Two new cobalt(II) coordination polymers, {[Co(L1)(tbta)] ·0.8H2O} n ( 1) and {[Co(L2)(tbta)] ·H2O} n ( 2) [L1 = 1,1′-(1,3-propanediyl)bis(2-methylbenzimidazole), L2 = 1,2-bis(2-methylbenzimidazole-1-ylmethyl)benzene, H2tbta = tetrabromoterephthalic acid] were obtained under hydrothermal conditions and structurally characterized by single-crystal X-ray diffraction methods, IR spectroscopy, TGA, and elemental analysis. The cobalt atoms present similar environments with tetrahedral arrangements in 1 and 2. The two complexes show a 2D (4,4) coordination network with sql topology. Compound 2 is further extended into a rare 3, 3, 4T3 three-dimensional supramolecular framework by weak C-H ···O hydrogen bonding interactions. The fluorescence and catalytic properties of the complexes for the degradation of the congo red azo dye in a Fenton-like process were investigated. [ABSTRACT FROM AUTHOR]

Abstract: A three-dimensional Co(II) metal–organic framework {[Co5(btec)2(btx)(μ 3-OH)2(H2O)2]·2H2O} n (1) (H4btec=1,2,4,5-benzenetetracarboxylic acid, btx=1,4-bis(1,2,4-triazol-1-ylmethyl)benzene) containing rare pentanuclear Co(II)-clusters has been hydrothermally synthesized and structurally characterized, and shows an unusual binodal (4,10)-connected topology. The fluorescence properties and catalytic activity of the complex for degradation of methyl orange in the Fenton-like process were investigated. [Copyright &y& Elsevier]

We report on the synthesis of ruthenium indenylidene catalysts [RuCl 2 (3-R-1-indenylidene)(PCy 3 ) 2 in which R is iso -propyl ( 7a ), tert -butyl ( 7b ) or cyclohexyl ( 7c )]. The obtained alkyl tagged indenylidene catalysts were analyzed by means of IR, elemental analysis, NMR and single crystal X-Ray diffraction analysis. Furthermore, the catalytic performance of these new complexes was examined in different metathesis reactions: ring-closing metathesis (RCM), ring-closing ene-yne metathesis (RCEYM), ring-opening metathesis polymerization (ROMP) and cross metathesis (CM), exhibiting a comparable activity in comparison with the commercially available catalyst 3a . [ABSTRACT FROM AUTHOR]

Three new ruthenium indenylidene complexes (I) are synthesized and their catalytic performance is examined in different metathesis reactions. [ABSTRACT FROM AUTHOR]

The microwave-assisted title reaction between N-protected 2-(2-bromoaryl)alkylpropargylamides and organo-boron compounds gives the corresponding 3-benzazepin-2-ones. [ABSTRACT FROM AUTHOR]