A new polymorph of N-(prop-2-yn­yl)tricyclo­[3.3.1.13,7]decane-1-carbox­amide

The alkynyl bond of the title compound, C14H19NO, has a length of 1.170 (5) Å. The amide function shows a trans conformation with respect to the carbonyl group characterized by the torsion angle O—C—N—H of −176 (2)°. There is an inter­molecular N—H⋯O hydrogen bond between the amide function and the carbonyl group. In addition, weak inter­molecular hydrogen bonds stabilize the crystal structure. A comparison with a polymorphic structure shows conformational differences with regard to the orientation of the carbonyl groups with respect to the adamantyl group [O—C—C—C = 96.2 (3)° in the title compound and 123.7 (2)° in the polymorph] and the orientations of the propargyl groups in relation to the carbonyl groups [O—C—C—C = −87.7 (3) and −58.7 (2)°, respectively]

Chlorido[3,3′-dibutyl-5,5′-(pyridine-2,6-di­yl)dipyrazol-1-ido]gold(III)

The Au atom in the C2-symmetric pincer-type title complex, [AuCl(C19H23N5)], is in the +3 oxidation state. The ligand is composed of one pyridine unit and two n-butyl-substituted pyrazoles (pyrz). Both pyrazoles are deprotonated, thus forming a neutral compound. To the best of our knowledge, this is the first AuIII–bis­pyrazolate complex. According to the special geometry in the N,N′,N′′-tridentate ligand, containing two five-membered heterocycles, the complex deviates from an ideal square-planar coordination geometry; the Npyrz—Au—Npyrz angle is 160.8 (3)°, indicating a distortion of nearly 20°

(Sp)-1-Diphenylphosphanyl-2-{(S)-[2-(diphenylphosphanyl)phenyl]hydroxymethyl}ferrocene

The absolute configuration of the title compound, [Fe(C5H5)(C36H29OP2)], is Sp at the ferrocene group and S at the asymmetric C atom. Both P atoms have a trigonal-pyramidal conformation. There is a short intramolecular C-H...P contact with an H...P distance of 2.56 Å. The hydroxy group is involved in an intramolecular O-H...[pi]phenyl interaction. The crystal packing shows five very weak intermolecular C-H...[pi] contacts, with H...Cg distances between 3.26 and 3.39 Å (Cg is the centroid of a phenyl or cyclopentadienyl ring). Key indicators: single-crystal X-ray study; T = 162 K; mean σ(C–C) = 0.004 Å; R factor = 0.038; wR factor = 0.083; data-to-parameter ratio = 22.3

Sesquicarbene Complexes:Bonding at the Interface Between M-C Single Bonds and M=C Double Bonds

Allylic dimetalated complexes [M2C(vinyl)]+ (M = Au(IPr) and Cr(CO)5 -) incorporate a new coordination mode of carbon. Digold complexes of this type have recently been detected experimentally. The intrinsic bond orbitals, partial charges, and structural parameters of the gold complexes and of chromium analogs were studied computationally and compared to those of the respective monometalated species and hydrocarbons. This showed that such digold complexes have a carbene character at both Au-C bonds comparable to typical carbene complexes of gold. Dichromium complexes with their stronger π-backdonation compete for interaction with carbon's π-orbital; each of the chromium atoms partakes in double bonding that is significant but weaker than that in the carbene analogs. Containing two M-C bonds on the interface between single and double bonds, these bridged complexes can be conceived as "sesquicarbene complexes". The π-system acted in a very adaptive manner and employed additional stabilization of the vinyl system only where needed. Significant carbene character is found simultaneously in both M-C bonds at the same carbon center. The discovery of these complexes with relatively strong double bond character between one carbon and two metal atoms could bring unusual single-carbon-centered organometallic cascade reactions to the horizon

Catalysis at the Heart of Success!

Bornscheuer, UT.; Hashmi, ASK.; García Gómez, H.; Rowan, MA. (2017). Catalysis at the Heart of Success!. ChemCatChem. 9(1):6-9. doi:10.1002/cctc.201601553S6991Bornscheuer, U. T. (2015). Biocatalysis: Successfully Crossing Boundaries. Angewandte Chemie International Edition, 55(14), 4372-4373. doi:10.1002/anie.201510042Bornscheuer, U. T. (2015). Biokatalyse: ein erfolgreicher Blick über den Tellerrand. Angewandte Chemie, 128(14), 4446-4447. doi:10.1002/ange.201510042Bornscheuer, U. T. (2009). Combined Success for Efficient Catalysis. ChemCatChem, 1(1), 5-5. doi:10.1002/cctc.200900144Weckhuysen, B. M. (2009). Crossing the Interfaces of Catalysis. ChemCatChem, 1(1), 7-7. doi:10.1002/cctc.200900146Kan, S. B. J., Lewis, R. D., Chen, K., & Arnold, F. H. (2016). Directed evolution of cytochrome c for carbon–silicon bond formation: Bringing silicon to life. Science, 354(6315), 1048-1051. doi:10.1126/science.aah621

Dichlorido(3-phenyl­indenyl­idene)bis­(triphenyl­phosphane)ruthenium(II) tetra­hydro­furan disolvate

The RuII atom in the title compound, [RuCl2(C15H10)(C18H15P)2]·2C4H8O, has a distorted square-pyramidal conformation. The P and Cl atoms are at the base of the pyramid and the Ru—Cindenyl­idene bond is in the axial position. The two Cl ligands and the two phosphane ligands are in trans positions. The Cl—Ru—Cl and P—Ru—P angles are 157.71 (2) and 166.83 (2)°, respectively. The two independent tetra­hydro­furan (THF) solvent mol­ecules are disordered. One THF mol­ecule was refined using a split-atom model. The second THF mol­ecule was accounted for by using program PLATON/SQUEEZE [Spek (2009 ▶). Acta Cryst. D65, 148–155]. The molecular conformation shows three intramolecular C—H⋯Cl contacts and two C—H⋯π interactions while the crystal packing features an intermolecular C—H⋯Cl contact and two very weak intermolecular C—H⋯π contacts

Proton supplier role of binuclear gold complexes in promoting hydrofunctionalisation of nonactivated alkenes

Density functional theory (DFT) was used to investigate PR 3 AuOTf-catalyzed hydrofunctionalisation of nonactivated alkenes using acetic acid and phenol where OTf = triflate (CF 3 SO 3- ). The gold(i) complex itself is found to be unlikely to operate as the π-activator due to its relatively low electrophilicity. Instead, the concurrent coordination of two gold(i) complexes to a nucleophile (PhOH or AcOH) enhances the acidity of the latter\u27s proton and causes the ensuing binuclear complex to serve as a strong proton supplier for activating the alkene π-bonds. Alternatively, the binuclear complex is also susceptible to produce a hidden HOTf. This hidden acid is accessible for hydrofunctionalization to occur but it is not in sufficient concentration to decompose the final product

Divergent gold-catalysed reactions of cyclopropenylmethyl sulfonamides with tethered heteroaromatics

Cyclopropenylmethyl sulfonamides with tethered heteroaromatics have been demonstrated to undergo divergent gold-catalysed cyclisation reactions. A formal dearomative (4+3) cycloaddition takes place with furan-tethered substrates, yielding densely functionalised 5,7-fused heterocycles related to the bioactive curcusone natural products. Indole-tethered substrates display divergent reactivity giving biologically important tetrahydro-β-carbolines via a Friedel-Crafts mechanism

3-(1H-Benzimidazol-2-yl)-2-chloro-8-methyl­quinoline

Two independent mol­ecules of the title compound, C17H12ClN3, are present in the structure. The angle between the planes defined by the atoms of the benzimidazole unit and the quinoline unit are 45.2 (3) and 44.0 (3)°, indicating an essentially identical conformation for both mol­ecules. Each of the independent mol­ecules is linked with a symmetry equivalent by an inter­molecular N—H⋯N hydrogen bond involving the two benzimidazole N atoms, to form chains in the crystallographic c direction

2-{2-[3-(1H-Benzimidazol-2-yl)quinolin-2-yl­oxy]eth­oxy}ethanol

In the title compound, C20H19N3O3, the inter­planar angle between the benzimidazole unit and the quinoline unit is 25.1 (2)°. Two different hydrogen bonds involving the hydr­oxy group and the imidazole unit are present. An intra­molecular N—H⋯O hydrogen bond links the hydr­oxy group of the side chain with the imidazole unit, forming a 12-membered ring, and an inter­molecular O—H⋯N hydrogen bond links the mol­ecules, forming chains in the crystallographic b direction