Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

Phd by thesis

J. Appl. Cryst.の発刊に際して

Co(II)/Ag(I) Synergistically Catalyzed Monoinsertion Reaction of Isocyanide to Terminal Alkynes with H2O: Synthesis of Alkynamide Derivatives.

Copper halide-chalcogenoether and -chalcogenone networks: Chain and cluster motifs, polymer dimensionality and photophysical properties

The title compound, C8H8Br4N2, crystallizes in the enanti­omorphic-defining space group P41212 and has a refined Flack x parameter of 0.04 (4). In the asymmetric unit, there are two half-mol­ecules; the whole mol­ecules (A and B) are generated by twofold rotation symmetry. In mol­ecule A, the twofold axis is normal to the pyrazine ring passing through the centre of the ring, while in mol­ecule B, the twofold rotation axis lies in the plane of the pyrazine ring bis­ecting the C—C aromatic bonds. The two mol­ecules are pseudo-mirror images of one another, and the best fit of the two mol­ecules was obtained for inverted mol­ecule B on mol­ecule A, with an r.m.s. deviation of 0.1048 A and a maximum deviation of any two equivalent atoms of 0.2246 A. In the crystal, the A mol­ecules are linked by weak C—H⋯Br hydrogen bonds and Br⋯Br inter­actions [3.524 (3) A], forming a three-dimensional framework. The B mol­ecules are also linked by weak C—H⋯Br hydrogen bonds and Br⋯Br inter­actions [3.548 (3) A], forming a three-dimensional network that inter­penetrates the network of A mol­ecules.

https://journals.iucr.org/e/issues/2014/08/00/hb0005/hb0005.pdf

Crystal structure of a tetra-kis-substituted pyrazine compound: 2,3,5,6-tetra-kis-(bromo-meth-yl)pyrazine.

The structure of trans-[Ni(CH3CN)2(H2O)4]Br2 has been determined at 153 K. The complex possesses Ci symmetry, with the NiII atom lying on an inversion center. The Ni atom is coordinated to four water mol­ecules in the equatorial plane and to two trans aceto­nitrile mol­ecules. In the crystal, a three-dimensional structure is formed by hydrogen bonding involving the lattice Br− ions and the coordinated water mol­ecules.

trans-Bis­(aceto­nitrile-N)­tetra­aqua­nickel(II) dibromide

The two new pyrazine­ophanes, 5,7-di­hydro-1H,3H-dithieno[3,4-b:3′,4′-e]pyrazine, C8H8N2S2, L1, and 3,4,8,10,11,13-hexa­hydro-1H,6H-bis­([1,4]di­thio­cino)[6,7-b:6′,7′-e]pyrazine, C12H16N2S4, L2, both crystallize with half a mol­ecule in the asymmetric unit; the whole mol­ecules are generated by inversion symmetry. The mol­ecule of L1, which is planar (r.m.s. deviation = 0.008 A), consists of two sulfur atoms linked by a rigid tetra-2,3,5,6-methyl­ene­pyrazine unit, forming planar five-membered rings. The mol­ecule of L2 is step-shaped and consists of two S–CH2–CH2–S chains linked by the central rigid tetra-2,3,5,6-methyl­ene­pyrazine unit, forming eight-membered rings that have twist-boat-chair con­fig­urations. In the crystals of both compounds, there are no significant inter­molecular inter­actions present. The reaction of L1 with silver nitrate leads to the formation of a two-dimensional coordination polymer, poly[(μ-5,7-di­hydro-1H,3H-dithieno[3,4-b;3′,4′-e]pyrazine-κ2S:S′)(μ-nitrato-κ2O:O′)silver(I)], [Ag(NO3)(C8H8N2S2)]n, (I), with the nitrato anion bridging two equivalent silver atoms. The central pyrazine ring is situated about an inversion center and the silver atom lies on a twofold rotation axis that bis­ects the nitrato anion. The silver atom has a fourfold AgO2S2 coordination sphere with a distorted shape. The reaction of L2 with silver nitrate also leads to the formation of a two-dimensional coordination polymer, poly[[μ33,4,8,10,11,13-hexa­hydro-1H,6H-bis­([1,4]di­thio­cino)[6,7-b;6′,7′-e]pyrazine-κ3S:S′:S′′](nitrato-κO)silver(I)], [Ag(NO3)(C12H16N2S4)]n, (II), with the nitrate anion coordinating in a monodentate manner to the silver atom. The silver atom has a fourfold AgOS3 coordination sphere with a distorted shape. In the crystals of both complexes, the networks are linked by C—H⋯O hydrogen bonds, forming supra­molecular frameworks. There are additional C—H⋯S contacts present in the supra­molecular framework of II.

https://journals.iucr.org/e/issues/2020/04/00/lh5951/lh5951.pdf

Silver(I) nitrate two-dimensional coordination polymers of two new pyrazine­thio­phane ligands: 5,7-di­hydro-1H,3H-dithieno[3,4-b:3′,4′-e]pyrazine and 3,4,8,10,11,13-hexa­hydro-1H,6H-bis­([1,4]di­thio­cino)[6,7-b:6′,7′-e]pyrazine

The title compounds, C32H28N2O4, (I), and C32H28N2S4, (II), respectively, are tetra­substituted pyrazines and both possess Ci symmetry They differ only in the hetero atom (X) of the –­CH2XPh side-arm substituents: X = O in (I) and S in (II) Compound (I) has an overall S-shape with a pair of adjacent –­CH2OPh side arms alternately above and below the plane of the central pyrazine ring The phenyl rings are inclined to one another by 1263 (18)° and there is one intra­molecular C—H⋯O hydrogen bond involving adjacent –CH2OPh side arms In compound (II), adjacent –CH2SPh side arms point in opposite directions with respect to the pyrazine ring plane, with the phenyl rings inclined at 6045 (8)° Both structures have weak C—H⋯π inter­molecular inter­actions

2,3,5,6-Tetrakis(phenoxymethyl)pyrazine and 2,3,5,6-tetrakis(phenylsulfanylmethyl)pyrazine.

The reaction of the ligand 2,3,5,6-tetra­kis­[(methyl­sulfanyl)­meth­yl]pyrazine (L1) with silver(I) nitrate led to {[Ag(C12H20N2S4)](NO3)}n, (I), catena-poly[[silver(I)-μ-2,3,5,6-tetra­kis­[(methyl­sulfan­yl)meth­yl]pyrazine] nitrate], a compound with a metal–organic chain structure. The asymmetric unit is composed of two half ligands, located about inversion centres, with one ligand coordinating to the silver atoms in a bis-tridentate manner and the other in a bis-bidentate manner. The charge on the metal atom is compensated for by a free nitrate anion. Hence, the silver atom has a fivefold S3N2 coordination sphere. The reaction of the ligand 2,3,5,6-tetra­kis­[(phenyl­sulfanyl)­meth­yl]pyrazine (L2) with silver(I) nitrate, led to [Ag2(NO3)2(C32H28N2S4)]n, (II), poly[di-μ-nitrato-bis­{μ-2,3,5,6-tetra­kis­[(phenyl­sulfan­yl)meth­yl]pyrazine}disilver], a compound with a metal–organic network structure. The asymmetric unit is composed of half a ligand, located about an inversion centre, that coordinates to the silver atoms in a bis-tridentate manner. The nitrate anion coordinates to the silver atom in a bidentate/monodentate manner, bridging the silver atoms, which therefore have a sixfold S2NO3 coordination sphere. The reaction of the ligand 2,3,5,6-tetra­kis­[(pyridin-2-yl­sulfanyl)­meth­yl]pyrazine (L3) with silver(I) nitrate led to [Ag3(NO3)3(C28H24N6S4)]n, (III), poly[trinitrato{μ6-2,3,5,6-tetra­kis[(pyri­din-2-ylsulfan­yl)meth­yl]pyrazine}­trisilver(I)], a compound with a metal–organic framework structure. The asymmetric unit is composed of half a ligand, located about an inversion centre, that coordinates to the silver atoms in a bis-tridentate manner. One pyridine N atom bridges the monomeric units, so forming a chain structure. Two nitrate O atoms also coordinate to this silver atom, hence it has a sixfold S2N2O2 coordination sphere. The chains are linked via a second silver atom, located on a twofold rotation axis, coordinated by the second pyridine N atom. A second nitrate anion, also lying about the twofold rotation axis, coordinates to this silver atom via an Ag—O bond, hence this second silver atom has a threefold N2O coordination sphere. In the crystal of (I), the nitrate anion plays an essential role in forming C—H⋯O hydrogen bonds that link the metal–organic chains to form a three-dimensional supra­molecular structure. In the crystal of (II), the metal–organic networks (lying parallel to the bc plane) stack up the a-axis direction but there are no significant inter­molecular inter­actions present between the layers. In the crystal of (III), there are a number of C—H⋯O hydrogen bonds present within the metal–organic framework. The role of the nitrate anion in the formation of the coordination polymers is also examined.

https://journals.iucr.org/e/issues/2017/03/00/wm5369/wm5369.pdf

Tokouré Assoumatine

Papers

Crystal structure of a tetra-kis-substituted pyrazine compound: 2,3,5,6-tetra-kis-(bromo-meth-yl)pyrazine.

trans-Bis(acetonitrile-N)tetraaquanickel(II) dibromide

Silver(I) nitrate two-dimensional coordination polymers of two new pyrazinethiophane ligands: 5,7-dihydro-1H,3H-dithieno[3,4-b:3′,4′-e]pyrazine and 3,4,8,10,11,13-hexahydro-1H,6H-bis([1,4]dithiocino)[6,7-b:6′,7′-e]pyrazine

2,3,5,6-Tetrakis(phenoxymethyl)pyrazine and 2,3,5,6-tetrakis(phenylsulfanylmethyl)pyrazine.

Silver(I) nitrate complexes of three tetra-kis-thio-ether-substituted pyrazine ligands: metal-organic chain, network and framework structures.

Tokouré Assoumatine

Papers

Crystal structure of a tetra-kis-substituted pyrazine compound: 2,3,5,6-tetra-kis-(bromo-meth-yl)pyrazine.

trans-Bis­(aceto­nitrile-N)­tetra­aqua­nickel(II) dibromide

Silver(I) nitrate two-dimensional coordination polymers of two new pyrazine­thio­phane ligands: 5,7-di­hydro-1H,3H-dithieno[3,4-b:3′,4′-e]pyrazine and 3,4,8,10,11,13-hexa­hydro-1H,6H-bis­([1,4]di­thio­cino)[6,7-b:6′,7′-e]pyrazine

2,3,5,6-Tetrakis(phenoxymethyl)pyrazine and 2,3,5,6-tetrakis(phenylsulfanylmethyl)pyrazine.

Silver(I) nitrate complexes of three tetra-kis-thio-ether-substituted pyrazine ligands: metal-organic chain, network and framework structures.

trans-Bis(acetonitrile-N)tetraaquanickel(II) dibromide

Silver(I) nitrate two-dimensional coordination polymers of two new pyrazinethiophane ligands: 5,7-dihydro-1H,3H-dithieno[3,4-b:3′,4′-e]pyrazine and 3,4,8,10,11,13-hexahydro-1H,6H-bis([1,4]dithiocino)[6,7-b:6′,7′-e]pyrazine