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

Recent developments in isocyanide based multicomponent reactions in applied chemistry

Multicomponent reactions (MCRs) are fundamentally different from two-component reactions in several aspects. Among the MCRs, those with isocyanides have developed into popular organic-chemical reactions in the pharmaceutical industry for the preparation of compound libraries of low-molecular druglike compounds. With a small set of starting materials, very large libraries can be built up within a short time, which can then be used for research on medicinal substances. Due to the intensive research of the last few years, many new backbone types have become accessible. MCRs are also increasingly being employed in the total synthesis of natural products. MCRs and especially MCRs with isocyanides offer many opportunities to attain new reactions and basic structures. However, this requires that the chemist learns the “language” of MCRs, something that this review wishes to stimulate.

Multicomponent Reactions with Isocyanides.

N-Heterocyclic carbenes have become universal ligands in organometallic and inorganic coordination chemistry. They not only bind to any transition metal, be it in low or high oxidation states, but also to main group elements such as beryllium, sulfur, and iodine. Because of their specific coordination chemistry, N-heterocyclic carbenes both stabilize and activate metal centers in quite different key catalytic steps of organic syntheses, for example, C-H activation, C-C, C-H, C-O, and C-N bond formation. There is now ample evidence that in the new generation of organometallic catalysts the established ligand class of organophosphanes will be supplemented and, in part, replaced by N-heterocyclic carbenes. Over the past few years, this chemistry has been the field of vivid scientific competition, and yielded previously unexpected successes in key areas of homogeneous catalysis. From the work in numerous academic laboratories and in industry, a revolutionary turning point in oraganometallic catalysis is emerging.

http://aether.cmi.ua.ac.be/artikels/Artikels%20Gitte/Artikels/Reviews/NHC-%20liganden%20Herrmann.pdf

N-heterocyclic carbenes: a new concept in organometallic catalysis.

We present a new class of dicationic palladium NHC complexes with two carbene ligands bearing different aryl substituents and a hemilabile pyrimidyl group. They can either be synthesized from the imidazolium salts via the silver transmetalation route to a halide-free palladium(II) precursor or by direct deprotonation by palladium acetate. For four complexes we could determine their solid-state structures by X-ray diffraction experiments. Insight gained by NMR spectroscopy and DFT calculations revealed that in solution the two potentially bidentate ligands interchange between chelating and non-chelating coordination modes. The preference of these coordination modes is governed by the steric influence of the different ligands. The complexes were shown to be active catalysts for the hydroarylation of alkynes, and their performance was rationalized by DFT calculations.

Electron-poor hemilabile dicationic palladium NHC complexes - synthesis, structure and catalytic activity.

Ein quadratisch-planarer Ruthenium(II)-Komplex mit Low-Spin- Konfiguration

Reaction of cyanamide and their derivatives with (η5-C5H5)Mn(CO)3 and (η5-C5H4CH3)Mn(CO)3

Bridge functionalized bis-N-heterocyclic carbene rhodium(I) complexes and their application in catalytic hydrosilylation

Four novel organorhenium(vii) oxides of the type L-ReO3 are presented: [4-(trifluoromethyl)phenyl]trioxorhenium 1b, [4-(trifluoromethoxy)phenyl]trioxorhenium 2b, [4-(trifluoromethyl)tetrafluorophenyl]trioxorhenium(THF) 3b·THF and (2,2,6,6-tetramethylpiperidin-1-yl)trioxorhenium 5 As intermediate products, the novel diarylzinc compounds bis[4-(trifluoromethoxy)phenyl]zinc 2a and bis[2,6-bis(trifluoromethyl)phenyl]zinc 4a were prepared The properties and structure of 1b-5 were studied by means of 1H, 13C, 19F and 17O NMR, IR, MS, TGA and elemental analysis Due to the strong Lewis acidity of the Re(vii) centres crystal structures of complexes 1b and 2b were obtained as THF adducts 1b·THF and 2b·THF Complexes 1b, 2b, 3b·THF and 5 have been examined as catalysts in olefin epoxidation using cis-cyclooctene as a model substrate Epoxide yields of around 80% and TOFs >1300 h-1 can be obtained with 1b, 2b and 3b·THF using TBHP as an oxidant in CDCl3 at 55 °C, exceeding the only reported catalytically active aryl trioxorhenium complex xylyltrioxorhenium (XTO) Moreover, 1b shows catalytic activity in the self-metathesis of 1-hexene with good yields using Et2AlCl as a co-catalyst Additionally, 1b and 5 were found to be efficient catalysts for the ring-opening metathesis polymerization (ROMP) of norbornene Polynorbornene with high molecular weight can be obtained in good yields at room temperature using RnAlCl3-n as a co-catalyst 5 is the first example of an amido trioxorhenium(vii) complex active in olefin metathesis

Eberhardt Herdtweck

Papers

Electron-poor hemilabile dicationic palladium NHC complexes - synthesis, structure and catalytic activity.

Ein quadratisch-planarer Ruthenium(II)-Komplex mit Low-Spin- Konfiguration

Reaction of cyanamide and their derivatives with (η5-C5H5)Mn(CO)3 and (η5-C5H4CH3)Mn(CO)3

Bridge functionalized bis-N-heterocyclic carbene rhodium(I) complexes and their application in catalytic hydrosilylation

Synthesis, characterization and application of organorhenium(VII) trioxides in metathesis reactions and epoxidation catalysis