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Ethynylbenziodoxol(on)e (EBX) cyclic hypervalent iodine reagents are now established reagents for the alkynylation of radicals and nucleophiles, yet they present limited possibilities for further structure and reactivity modification. Herein, the first synthesis is reported for the corresponding ethynylbenziodazolone (EBZ) reagents, in which the oxygen atom in the iodoheterocycle is replaced by a nitrogen atom. The substituent on the nitrogen enables further fine‐tuning of the reagent structure and reactivity. EBZ reagents are obtained easily from the corresponding benzamides by using a one‐step procedure, and display reactivity comparable to that of EBX reagents. In particular, they are applied in an asymmetric copper‐catalyzed oxyalkynylation of diazo compounds, which proceeds in high yield and enantioselectivity for a broad range of substituents on the diazo compounds and the alkyne. [ABSTRACT FROM AUTHOR]

Vinyl triazenes are potentially interesting compounds for synthetic organic and medicinal chemistry, but synthetic routes to make olefins with triazene groups are still scarce. In this work, we show that vinyl triazenes are accessible by Pd‐catalyzed addition reactions to alkynyl triazenes. Hydrogenation, hydroarylation, and haloallylation reactions allow preparing mono‐, di‐ and trisubstituted vinyl triazenes in high yields, and with good regio‐ and stereoselectivities. [ABSTRACT FROM AUTHOR]

A new procedure for the synthesis of highly substituted 1,3-diaminopyrazoles is described. As substrates, we have employed 1-alkynyltriazenes and imines. The formation of pyrazoles was achieved by two-fold C-N coupling reactions in the presence of (JohnPhos)AuCl and Ag NTf2 as catalyst precursors. The regioselectivity of the reaction was inferred from a crystallographic analysis of one reaction product. [ABSTRACT FROM AUTHOR]

Actinide oxo clusters are an important class of compounds due to their impact on actinide migration in the environment. The photolytic reduction of uranyl(VI) has potential application in catalysis and spent nuclear fuel reprocessing, but the intermediate species involved in this reduction have not yet been elucidated. Here we show that the photolysis of partially hydrated uranyl(VI) in anaerobic conditions leads to the reduction of uranyl(VI), and to the incorporation of the resulting UV species into the stable mixed-valent star-shaped UVI/UV oxo cluster [U(UO2)5(μ3-O)5(PhCOO)5(Py)7] ( 1). This cluster is only the second example of a UVI/UV cluster and the first one associating uranyl groups to a non-uranyl(V) center. The UV center in 1 is stable, while the reaction of uranyl(V) iodide with potassium benzoate leads to immediate disproportionation and formation of the U12IVU4VO24 cluster {[K(Py)2]2[K(Py)]2[U16O24(PhCOO)24(Py)2]} ( 5). [ABSTRACT FROM AUTHOR]

Valorization of CO2, an abundant C(1) synthon, into platform chemicals is of growing interest. In this context, a key reaction is the cycloaddition of CO2 to epoxides to form carbonates (CCE). A series of organocatalysts for this reaction, based on imidazolium salts modified with a styrene functional group and a second variable functional group, were prepared and characterized. Both the ionic salts and ionic polymers derived from the salts were evaluated in this reaction. In general, the monomers perform slightly better than the polymers; however, the latter are considerably more convenient to use. Of the catalysts studied, the ionic polystyrene imidazolium salt with an ammonium functionality shows highest activity, tolerates a range of epoxides, and can be recycled multiple times without loss of activity. [ABSTRACT FROM AUTHOR]

Platform chemicals are usually derived from petrochemical feedstocks. A sustainable alternative commences with lignocellulosic biomass, a renewable feedstock, but one that is highly challenging to process. Ionic liquids (ILs) are able to solubilize biomass and, in the presence of catalysts, convert the biomass into useful platform chemicals. Herein, we demonstrate that mixtures of ILs are powerful systems for the selective catalytic transformation of cellulose into 5-hydroxymethylfurfural (HMF). Combining ILs with continuous HMF extraction into methyl-isobutyl ketone or 1,2-dimethoxyethane, which form a biphase with the IL mixture, allows the online separation of HMF in high yield. This one-step process is operated under relatively mild conditions and represents a significant step forward towards sustainable HMF production. [ABSTRACT FROM AUTHOR]

The nickel(II) hydride complex [(MeN2N)Ni-H](2) was synthesized by the reaction of [(MeN2N)Ni-OMe] (6) with Ph2SiH2and was characterized by NMR and IR spectroscopy as wellas X-ray crystallography. 2was unstable in solution,and it decomposed via two reaction pathways. The first pathway wasintramolecular N–H reductive elimination to give MeN2NH and nickel particles. The second pathway was intermolecular,with H2, nickel particles, and a five-coordinate Ni(II)complex [(MeN2N)2Ni] (8) as the products. 2reacted with acetone and ethylene,forming [(MeN2N)Ni-OiPr] (9) and [(MeN2N)Ni-Et] (10), respectively. 2also reacted with alkylhalides, yielding nickel halide complexes and alkanes. The reductionof alkyl halides was rendered catalytically, using [(MeN2N)Ni-Cl] (1) as catalyst, NaOiPr or NaOMe as base, and Ph2SiH2or Me(EtO)2SiH as the hydride source. The catalysis appearsto operate via a radical mechanism. [ABSTRACT FROM AUTHOR]

The Back Cover picture represents the conversion of lignocellulose into the renewable building block HMF using a mixture of designer ionic liquids that work together in unison. More details can be found in the Full Paper by Siankevich et al. on page 2089 in Issue 16, 2016 (DOI: 10.1002/cssc.201600313). [ABSTRACT FROM AUTHOR]

Thestrongly chelating anionic β-diketiminate ligand hasbeen employed to formulate complexes involving almost every metalof the periodic table; however, the heavier metals of the d blockremain relatively unexplored. This paper describes the synthesis andcharacterization of the first two osmium β-diketiminato compounds,including a coordinatively unsaturated cationic complex. In parallelto the analogous Ru(II) complexes, the cationic (η6-arene)osmium(II) complex demonstrates bifunctional behavior through[4 + 2] cycloaddition with ethylene, cleavage of dihydrogen undermild conditions, and protonation/chloride addition with [Et2OH]Cl. Metal-centered activity in both the Ru(II) and Os(II) β-diketiminateshas until now remained elusive, as the cationic Os complex is shownto readily coordinate an aryl isonitrile. The applicability of Os(II)β-diketiminato complexes in catalytic olefin hydrogenation demonstratessignificantly greater activity in terms of conversion and TOF fora range of substrates, including styrene, cyclohex-1-ene, and 1-methylcyclohex-1-ene.Moreover, selective hydrogenation of the exocyclic alkenyl group inlimonene was observed, whereas the corresponding isostructural Ru(II)complexes are inactive. In contrast, the cationic (η6-arene)ruthenium(II) β-diketiminato complex proved more activefor the catalytic dehydrogenation of N,N-dimethylamine borane (Me2NBH3) than the equivalentOs(II) species. A detailed DFT study of the Ru(II) and Os(II) β-diketiminatospecies using charge decomposition analysis (CDA) demonstrates differencesin metal–ligand interactions, which in turn considerably influencesthe extent of bifunctional reactivity. [ABSTRACT FROM AUTHOR]

Abstract: Two new bis(diphenylphosphino)amines, N,N-bis(diphenylphosphino)benzidine 1 and N,N-bis(diphenylphosphino)-3,3-dimethoxybenzidine 2 were prepared by aminolysis. Their corresponding oxides, sulfides and selenides were readily prepared by reaction with hydrogen peroxide, elemental sulfur or grey selenium, respectively. Symmetric dinuclear palladium and platinum complexes were also isolated from the reaction with [M(cod)Cl2] (M=Pd or Pt, cod=cycloocta-1,5-diene). All compounds were characterized by IR and NMR spectroscopy and elemental analysis and the structure of [(Ph2P)2N–C6H4–C6H4–N(PPh2)2] was determined by single crystal X-ray diffraction. The catalytic activity of palladium complexes in Suzuki coupling reactions was also investigated. [Copyright &y& Elsevier]

Abstract: Imidazolium salts with aromatic groups 1,3-bis(9-anthracenylmethyl)imidazolium chloride ([Bamim]Cl), 1,3-bis(1-naphthalenylmethyl)imidazolium chloride ([Bnmim]Cl) and 1,3-bis(benzylmethyl)imidazolium chloride ([Bbmim]Cl) were reacted with PdCl2 forming the analogous tetrachloropalladate salts. These palladium-containing salts were evaluated as pre-catalysts in Suzuki cross-coupling reactions in ionic liquids generally resulting in high conversions. The formation of palladium nanoparticles is observed and their role in the overall catalytic mechanism is discussed. [Copyright &y& Elsevier]

A structure-activity study was carried out for Ni catalyzed alkyl-alkyl Kumada-type cross coupling reactions. A series of new nickel(II) complexes including those with tridentate pincer bis(amino)amide ligands (RN2N) and those with bidentate mixed amino-aniide ligands (RNN) were synthesized and structurally characterized. The coordination geometries of these complexes range from square planar, tetrahedral, to square pyramidal. The complexes had been examined as precatalysts for cross coupling of nonactivated alkyl halides, particularly secondary alkyl iodides, with alkyl Grignard reagents. Comparison was made to the results obtained with the previously reported Ni pincer complex [(MeN2N)NiCl] A transmetajation site in the precatalysts is necessary for the catalysis. The coordination geometries and spin-states of the precatalysts have a small or no influence. The work led to the discovery of several well-defined Ni catalysts that are significantly more active and efficient than the pincer complex [(MeN2N)NiCl] for the coupling of secondary alkyl halides. The best two catalysts are [(HNN)Ni(PPh3)Cl] and [(HNN)Ni(2,4-lutidine)Cl] The improved activity and efficiency was attributed to the fact that phosphine and lutidine ligands in these complexes can dissociate from the Ni center during catalysis. The activation of alkyl halides was shown to proceed via a radical mechanism. [ABSTRACT FROM AUTHOR]

Abstract: Four new bis(phosphino)amine ligands (Ph2P)2N-C6H3-R, where R=3,5-OMe (1), 2,5-OMe (2), 2,4-OMe (3) or 3,4-OMe (4), were prepared via aminolysis of the corresponding dimethoxyanilines with 2equiv. of diphenylphosphine chloride in the presence of triethyl amine. Oxidation of these ligands with aqueous H2O2, elemental S8 or Se powder afforded the corresponding chalcogen oxides 1a–4a, sulfides 1b–4b and selenides 1c–4c in good yields. Reaction of 1–4 with [MCl2(cod)] (M=Pt, Pd; cod=cycloocta-1,5-diene) in equimolar ratios afforded cis-[MCl2{(Ph2P)2N-C6H3-R}] (M=Pt; R=3,5-OMe 1d, R=2,5-OMe 2d, R=2,4-OMe 3d, and R=3,4-OMe 4d. M=Pd; R=3,5-OMe 1e, R=2,5-OMe 2e, R=2,4-OMe 3e, and R=3,4-OMe 4e). Similarly, reaction of [Cu(CH3CN)4]PF6 with the 1–4 in 1:2 ratio gave [Cu{(Ph2P)2N-C6H3-R}2]PF6 (R=3,5-OMe 1f, 2,5-OMe 2f, 2,4-OMe 3f and 3,4-OMe 4f). All new compounds were fully characterized by spectroscopy and elemental analysis and the molecular structures of seven representative compounds were determined by single-crystal X-ray crystallography. In addition, the palladium complexes were investigated as pre-catalysts in C–C coupling reactions. [Copyright &y& Elsevier]

Two new aminophosphines, benzyl-N(Ph2P)2 and 2-picolyl-N(Ph2P)2, have been synthesized. Oxidation of the aminophosphines with either hydrogen peroxide, elemental sulfur and selenium gave the corresponding oxides, sulfides and selenides benzyl-N(Ph2P=E)2 and 2-picolyl-N(Ph2P=E)2, where E = O, S, or Se. Complexes [benzyl-N(Ph2P)2]MCl2 and [2-picolyl-N(Ph2P)2]MCl2, where M = Pd, Pt, were obtained by the reaction of the aminophosphines with MCl2(cod). The new compounds were characterised by NMR, IR spectroscopy and microanalysis. Furthermore, representative solid-state structures of the palladium and platinum complexes were determined using single crystal X-ray diffraction analysis. The palladium complexes were further investigated as potential catalysts in C–C coupling reactions. [Copyright &y& Elsevier]

The article reports on the discovery of multiple carbon-chloride (C-Cl) activation reactions on CH2Cl2 and CHCL3. The authors report that the reactions led to selective C-C bond formations which enable the first catalytic couplings of CH2Cl2 with Grignard reagents.