Abstract: The invention comprises a chemical composition with the structure shown below. The composition can be polymerized or pyrolyzed, forming transition metal nanoparticles homogeneously dispersed in a thermoset or carbon composition. The size of the nanoparticles can be controlled by manipulating the number and arrangement of functional groups in the composition and by changing the conditions of the polymerization or pyrolysis. The resulting thermosets and carbon compositions have useful magnetic, electric, mechanical, catalytic and/or optical properties.

Abstract: The present invention relates to a non-aqueous electrolyte additive for improving safety and a lithium secondary battery comprising the same, and more particularly to a non-aqueous electrolyte additive that can improve cycle life and safety properties of a lithium ion secondary battery.

Abstract: The present invention relates to a non-aqueous electrolyte additive for improving safety and a lithium secondary battery comprising the same, and more particularly to a non-aqueous electrolyte additive that can improve cycle life and safety properties of a lithium ion secondary battery.

Abstract: Compounds and metal complexes comprising a polycyclic, fused ring ligand or inertly substituted derivative thereof having up to 60 atoms other than hydrogen, said ligand comprising at least: (1) a cyclopentadienyl ring, (2) a 6, 7, or 8 membered ring other than a 6-carbon aromatic ring, and (3) an aromatic ring, with the proviso that said 6, 7, or 8 membered ring (2), is fused to both the cyclopentadienyl ring (1), and the aromatic ring (3), polymerization catalysts, a process to prepare the novel compounds and complexes, and olefin polymerization processes using the same are disclosed.

Abstract: The invention relates to structural subunits called “synthons” which are suitable for use in the design and manufacture of molecular nanostructures, machines, and devices. The synthon comprises polyhedra units and other species which exhibit rigid structural frameworks, the availability of stereo- and regiochemically directed substitution patterns, synthetic availability and accessability with substitutional control, diversity of available structural arrangements with said polyhedra units and related species, and connecting means which function to join adjacent synthons.

Abstract: A process for producing high-purity hydrotalcites by reacting alcohols or alcohol mixtures with at least one or more divalent metal(s) and at least one or more trivalent metal(s) and hydrolyzing the resultant alcoholate mixture with water. The corresponding metal oxides can be produced by calcination.

Abstract: The present invention relates to catalyst systems, processes for making such catalysts, intermediates for such catalysts, and olefin polymerization processes using such catalysts wherein such catalyst includes a component represented by the following formula 1A: wherein R and R′ independently represent a hydrogen atom, or a substituted or unsubstituted, branched or unbranched hydrocarbyl or organosilyl radical; R1, R2, and R3 independently represent a hydrogen atom, or a substituted or unsubstituted, branched or unbranched hydrocarbyl radical; M is a group IIIB, IVB, VB, VIB, VIIB or VIII transition metal; T independently represents a univalent anionic ligand such as a hydrogen atom, or a substituted or unsubstituted hydrocarbyl halogeno, aryloxido, arylorganosilyl, alkyloriganosilyl, amido, arylamido, phosphido, or arylphosphido group, or two T groups taken together represent an alkylidene or a cyclometallated hydrocarbyl bidentate ligand; L independently represents a sigma donor

Abstract: The ability to design and construct solid-state materials with pre-determined structures is a grand challenge in chemistry. An inventive strategy based on reticulating metal ions and organic carboxylate links into extended networks has been advanced to a point that has allowed the design of porous structures in which pore size and functionality can be varied systematically. MOF-5, a prototype of a new class of porous materials and one that is constructed from octahedral Zn—O—C clusters and benzene links, was used to demonstrate that its 3-D porous system can be functionalized with the organic groups, —Br, —NH2, —OC3H7, —OC5H11, —H4C2, and —H4C4, and its pore size expanded with the long molecular struts biphenyl, tetrahydropyrene, pyrene, and terphenyl.

Abstract: A catalyst component for addition polymerization composed of a transition metal compound (A) of the following general formula [1]:

Abstract: New metallocene compounds are described where the ligand contains at least one open-pentadienyl containing radical characterized by a cyclic or acyclic, six &pgr; electron, delocalized, five atomic center structure. These metallocenes can advantageously be used in catalyst systems for the polymerization of olefins to generate a wide variety of different polymers including HDPE, LLDPE, ethylenelpropylene/(diene) elastomers, tactiospecific C3+&agr;-olefin polymers, intimate mixture thereof and the like.

Abstract: The invention relates to novel aminocarboxylate ligands that are suitable for complexing with a radionuclide, and are useful as therapeutic agents and as imaging agents for diagnostic purposes. In accordance with the present invention, a method of preparing a compound of formula fac-[M(CO)3(OH2)3]+  (I) wherein M is Mn, 99mTc, 186Re or 188Re, involves reacting a metal in permetallate form with carbon monoxide and stannous ion. The compound of formula (I) can be reacted with a ligand Lx to form a compound of the formula fac-[M(CO)3Lx]n  (II) wherein M is as defined above, Lx is a monodentate or multidentate ligand or a mixture of these ligands, and n is a charge of the ligand Lx increased with one + charge. The invention also is directed to novel compounds, and kits for carrying out the disclosed methods.

Abstract: The invention relates to novel targeting drug agents that are targeted for entry into the mitochondria. More specifically, the agents are cisplatin derivatives called mitoplatins which are useful as anti-tumor agents. Mitoplatins are named for their targeting to the mitochondrial DNA via the carnitine-acylcarnitine translocase system. The invention also relates to methods of synthesizing mitoplatins, compositions of matter containing mitoplatins and methods of using the mitoplatins.

Abstract: An organic aluminoxy compound which shows 27Al nuclear magnetic resonance spectrum (27Al-NMR spectrum) having an A1/A2 ratio of at most 0.1, wherein A1 is area of a region encompassed by a segment of a line which connects a local minimum point existing between a continuous curve “a” containing a peak appearing at around 150 ppm and a continuous curve “b” containing a peak appearing at around 60 ppm to the point where the above curve “b” comes into contact with the base line and also by the above curve “b” and A2 is area of a region encompassed by the above curves “a” and “b” and also by the base line; an organic aluminoxy compound containing at least 5%, expressed in terms of aluminum atom, of a portion insoluble in a mixed solvent of toluene and hexane in a ratio by volume of 2:5 at 30° C. or lower; and a catalyst for producing a polymer comprising any of the above organic aluminoxy compounds and a transition metal compound.

Abstract: A method of generating a electrochemiluminescent emission, which comprises exposing an electrochemiluminescent label linked to a coreactant, to conditions suitable for inducing electrochemiluminescence; said compound; a system for generating an electrochemiluminescent emission, which comprises said compound, means for exposing said compound to electrochemical energy, and means for detecting or measuring luminescence emitted from said compound or a composition containing same; and a kit for performing an assay using said compound.

Abstract: A process for producing high-purity hydrotalcites by reacting alcohols or alcohol mixtures with at least one or more divalent metal(s) and at least one or more trivalent metal(s) and hydrolysing the resultant alcoholate mixture with water. The corresponding metal oxides can be produced by calcination.

Abstract: The present invention relates to a process for the preparation of organorhenium oxides from rhenium-containing compounds, where the rhenium-containing compound is reacted with a silylating agent and organylating reagent, and the rhenium-containing compound originates in particular from the residue from a spent organorhenium oxide catalyst or rhenium oxide catalyst.

Abstract: A metal hydride derivative wherein at least one hydrogen atom is replaced by deuterium (.sup.2.sub.1 H) or tritium (.sup.3.sub.1 H) isotope. The metal constituent of such metal hydride may be a Group III, IV or V metal or a transition metal, e.g., antimony, aluminum, gallium, tin, or germanium. The isotopically stabilized metal hydride derivatives of the invention are useful as metal source compositions for chemical vapor deposition, assisted chemical vapor deposition (e.g., laser-assisted chemical vapor deposition, light-assisted chemical vapor deposition, plasma-assisted chemical vapor deposition and ion-assisted chemical vapor deposition), ion implantation, molecular beam epitaxy, and rapid thermal processing.

Abstract: Polysubstituted cyclopentadiene-containing compound, in which at least one substituent is has the formula --RDR'.sub.n, in which R is a linking group between the cyclopentadiene and the DR'.sub.n group, D is a hetero atom selected from group 15 or 16 of the Periodic Table of Elements or an aryl group, in which case R has at least the length of an ethylene group, R' is a hydrocarbon radical containing 1-20 carbon atoms (e.g., alkyl, aryl, aralkyl,. and the like, including straight chain, branched, cyclic, and derivatives thereof, and n is the number of R' groups bound to D (note that the R' groups may be identical or different).

Abstract: Compositions and methods for the solid phase synthesis of organic compounds are provided. The compositions are solid supports having an attached traceless linker precursor and are represented by the formula: ##STR1## In this formula, S.sup.0 is a solid support; B is a connecting group; M is a transition metal, for example ruthenium, chromium, iron, molybdenum and manganese; each L is independently a transition metal ligand; the letter n represents an integer of from 1 to 4, such that M has a sufficient number of ligands to fill the available valences; and X.sup.- represents an anion which is typically a non-nucleophilic anion.

Abstract: An organic aluminoxy compound which shows .sup.27 Al nuclear magnetic resonance spectrum (.sup.27 Al-NMR spectrum) having an A.sub.1 /A.sub.2 ratio of at most 0.1, wherein A.sub.1 is area of a region encompassed by a segment of a line which connects a local minimum point existing between a continuous curve "a" containing a peak appearing at around 150 ppm and a continuous curve "b" containing a peak appearing at around 60 ppm to the point where the above curve "b" comes into contact with the base line and also by the above curve "b" and A.sub.2 is area of a region encompassed by the above curves "a" and "b" and also by the base line; an organic aluminoxy compound containing at least 5%, expressed in terms of aluminum atom, of a portion insoluble in a mixed solvent of toluene and hexane in a ratio by volume of 2:5 at 30.degree. C. or lower; and a catalyst for producing a polymer comprising any of the above organic aluminoxy compounds and a transition metal compound.

Abstract: This invention relates to a process for polymerizing ethylene comprising contacting ethylene and optional comonomers with a catalyst system comprising an activator and a transition metal compound represented by the formula: ##STR1## Wherein R.sub.1 and R2 are independently hydrogen or a group having up to 100 carbon atoms, Cp.sub.1 is a bulky ligand; Cp.sub.2 is a bulky ligand or a heteroatom optionally bound to a C.sub.1 to C.sub.50 hydrocarbyl group, n is the valence state of the transition metal, Tm is a Group 3 to 10 metal, and each X is independently an anionic leaving group.

Abstract: A novel metallocene catalyst for the polymerization of olefin (co)polymers is of the general formula:R--SO.sub.2 --L--M--(X).sub.m T.sub.nwherein,M is a metal selected from Groups 3-10;T is a polymerization-stable anionic ancillary ligand;m+n is the valency of M minus 1;R is a C.sub.1 -C.sub.20 alkyl group, a C.sub.6 -C.sub.20 aryl ring or a C.sub.6 -C.sub.20 alkaryl or aralkyl group, optionally substituted with a halogen or an alkoxy group up to 10 carbon atoms;X is a halogen, alkoxy from C.sub.1 to C.sub.20, siloxy from C.sub.1 to C.sub.20, N(R).sub.2, a hydrocarbyl group containing up to about 12 carbon atoms, hydrogen or another univalent anionic ligand, or mixtures thereof;L is T as defined above with the proviso that one of the sites available for substitution is the attachment site of the sulfonyl group; andwherein L and T may be bridged.

Abstract: The present invention relates to a novel fullerene-containing metallocene. Such a fullerene-containing metallocene can be used as the catalyst for preparing olefin polymers.

Abstract: Catalyst component for the polymerization of alpha-olefins of general formula (I) ##STR1## wherein: M is a transition metal of groups 3, 4-10, lanthanide or actinide of the periodic table of the elements; A is a ring with delocalized .pi. electrons, L is a neutral Lewis base; m is an integer whose value can be: 0 or 1; E is selected from the group comprising: BR.sup.II, CR.sup.II.sub.2, SiR.sup.II.sub.2, GeR.sup.II.sub.2 ; Hal is selected from the group comprising iodine, bromine or chlorine; R.sup.III has the same meaning of R.sup.II ; Si is a silicon atom; D is selected from the group comprising: O, S, NR.sup.IV, PR.sup.IV, OR.sup.IV, SR.sup.IV, NR.sup.IV.sub.2, PR.sup.IV.sub.2 ; each X group equal to or different from each other is selected from the group comprising hydrogen, halide, alkyl, cycloalkyl, aryl, alkenyl, arylallyl, arylalkenyl or alkylaryl with 1 to 20 carbon atoms, n is a number whose value can be: 0, 1, 2 or 3, in order to full the remaining valences of metal M.

Abstract: There is provided a method for making a monovalent inorganic anion-intercalated hydrotalcite-like material by first reacting a magnesium-containing powder and a transition alumina powder in a carboxylic acid-free, aqueous suspension to form a meixnerite intermediate. This intermediate is then contacted with a monovalent inorganic anion, in its acid or soluble salt form, to make a hydrotalcite-like material. The latter is then separated from the suspension. Representative materials include a bromide-, chloride-, nitrate- or vanadate-intercalated, hydrotalcite-like material.

Abstract: There is provided a method for making a polyvalent inorganic anion-intercalated hydrotalcite-like material by first reacting a magnesium-containing powder and a transition alumina powder in a carboxylic acid-free, aqueous suspension to form a meixnerite intermediate. This intermediate is then contacted with a polyvalent inorganic anion, in its acid, acid salt or ammonium salt form, to make a hydrotalcite-like material. The latter is then separated from the suspension. Representative materials include a borate- metatungstate- and paramolybdate-intercalated hydrotalcite-like material.

Abstract: There is provided a method for making a divalent inorganic anion-intercalated hydrotalcite-like material by first reacting a magnesium-containing powder and a transition alumina powder in a carboxylic acid-free aqueous suspension to form a meixnerite intermediate. This intermediate is then contacted with a divalent inorganic anion, in its acid, acid salt or ammonium salt form, to make a hydrotalcite-like material. The latter is then separated from the suspension. Representative materials include a sulfate- and metavanadate-intercalated hydrotalcite-like material.

Abstract: There is provided an improved method for making synthetic hydrotalcite by first reacting a divalent metal compound with a trivalent metal oxide powder in a carboxylic acid-free, aqueous solution or suspension to form an intermediate. This intermediate is then contacted with an anion source such as carbon dioxide; a carbonate-containing compound; an acid or an ammonium salt to form a layered double hydroxide having the formula:A.sub.1-x B.sub.x (OH).sub.2 C.sub.z.mH.sub.2 O, where A represents a divalent metal cation, B represents a trivalent metal cation, C represents a mono- to polyvalent anion, and x, z and m satisfy the following conditions: 0.09<x<0.67; z=x/n, where n=the charge on the anion; and 2>m>0.5. Said layered double hydroxide is typically separated from the suspension by filtering, centrifugation, vacuum dehydration or other known means.

Abstract: There is provided a method for making monovalent organic anion-intercalated hydrotalcite-like materials by first reacting a magnesium-containing powder and a transition alumina powder in a carboxylic acid-free, aqueous suspension to form a meixnerite intermediate. This intermediate is then contacted with a monovalent organic anion to form a hydrotalcite-like material. The latter is then separated from the suspension. Representative materials include a stearate-, acetate- or benzoate-intercalated hydrotalcite-like material.

Abstract: There is provided an improved method for making synthetic hydrotalcite by first reacting powdered magnesium oxide with a high surface area, transition alumina in a solution or suspension to form a meixnerite-like intermediate. This intermediate is then contacted with an anion source such as an acid, and most preferably carbon dioxide, to form the layered double hydroxide which is separated from the suspension by filtering, centrifugation, vacuum dehydration or other known means. On a preferred basis, the transition alumina combined with activated magnesia consists essentially of an rehydratable alumina powder having a surface area of 100 m.sup.2 /g or greater. To make related double hydroxide compounds, still other reactants such as bromides, chlorides, boric acids, or salts thereof, may be substituted for the carbon dioxide gas fed into this suspension.

Abstract: Novel onium borates of an element of Groups 15 to 17 of the Periodic Table, or borates of an organometallic complex of an element of Groups 4 to 10 of the Periodic Table, well suited for the photochemical/electron beam cationic initiation of polymerization/crosslinking, the anionic borate moiety of which having the formula:[BX.sub.a R.sub.b ].sup.-in which a and b are integers ranging from 0 to 4 and a+b=4; the symbols X are each a halogen atom when a ranges up to 3 and an OH functional group when a ranges up to 2; and the symbols R, which may be identical or different, are each a phenyl radical substituted by at least one element or electron-withdrawing substituent or by at least two halogen atoms, or an aryl radical containing at least two aromatic ring members, or such aryl radical bearing at least one electron-withdrawing substituent.

Abstract: Metallocenes are prepared by a process in which a metal salt is reacted with at least one alkali metal and with an unsaturated, cyclic hydrocarbon in the presence of a solvent in one reaction step.

Abstract: A novel catalyst comprising the formula:LRE(O)nwhereinL is selected from the group consisting of(a) (R.sub.1)(AL)wherein R.sub.1 is an alkyl side chain containing at least one carbon-rhenium covalent bond, andAL is a molecule having C.sub.2 to C.sub.50, and has at least one hetero atom selected from the group consisting of N, O, S, and P wherein there is at least one hetero-rhenium dative bond, and has at least one chiral center. and(b) R.sub.AL is a straight or branched chain alkyl or arylalkyl group containing C.sub.2 to C.sub.50 and containing at least one heteroatom selected from the group consisting of N, O, S, and P, with the proviso that said alkyl group contains at least one carbon-rhenium covalent bond and at least one hetero-rhenium dative bond, and has at least one chiral center:and n is an integer which is 2, 3, 4, or 5 and which has utility in areas such as epoxidation of olefins.

Abstract: Electrochemiluminescent moieties having the formula(Re(P).sub.m (L.sup.1).sub.n (L.sup.2).sub.o (L.sup.3).sub.p (L.sup.4).sub.t (B).sub.uwhereinP is a polydentate ligand of Re;L.sup.1, L.sup.2, L.sup.3 and L.sup.4 are ligands of Re, each of which may be the same as or not the same as each other ligand;B is a substance which is a ligand of Re or is conjugated to one or more of P, L.sup.1, L.sup.2, L.sup.3 and L.sup.4 ;m is an integer equal to or greater than 1;each of n, o, p, q, r and s is zero or an integer;t is an integer equal to or greater than 1; andu is an integer equal to or greater than 1;P, L.sup.1, L.sup.2, L.sup.3, L.sup.4 and B being of such composition and number that the chemical moiety can be induced to electrochemiluminesce and the total number of bonds to Re provided by the ligands of Re being equal to the coordination number of Re are disclosed.

Abstract: There is provided a method for making a divalent or polyvalent organic anion-intercalated hydrotalcite-like materials by first reacting a magnesium-containing powder and a transition alumina powder in an aqueous suspension to form a meixnerite intermediate. This intermediate is then contacted with a dicarboxylate or polycarboxylate anion to form a hydrotalcite-like material. The latter is then separated from the suspension. Representative materials include an oxalate-, succinate- or terephthalate-intercalated hydrotalcite-like material.

Abstract: Novel onium borates of an element of Groups 15 to 17 of the Periodic Table, or borates of an organometallic complex of an element of Groups 4 to 10 of the Periodic Table, well suited for the photochemical/electron beam cationic initiation of polymerization/crosslinking, the anionic borate moiety of which having the formula:[BX.sub.a R.sub.b ].sup.-which a and b are integers ranging from 0 to 4 and a+b=4; the symbols X are each a halogen atom when ranges up to 3 and an OH functional group when a ranges up to 2; and the symbols R, which may be identical or different, are each a phenyl radical substituted by at least one element or electron-withdrawing substituent or by at least two halogen atoms, or an aryl radical containing at least two aromatic ring members, or such aryl radical bearing at least one electron-withdrawing substituent.

Abstract: Transition metal compounds of a crystalline-like structure are provided having unique electrical properties. The compounds comprising nickel have been shown to have ferromagnetic behavior which is induced or enhanced by exposure to electromagnetic radiation and heat. The compounds are identified by characteristic peaks in the infrared spectra and X-ray powder diffraction spectra. The spectra suggest the compounds have a planar structure of the empirical formula M(X).sub.(4-Y)/X M.sub.C (Y)C.sub.4 or a three-dimensional structure of empirical formula M(X).sub.(6-Y)/X M.sub.C (Y)C.sub.6, wherein M.sub.C (Y) is the transition metal, with Y being its ionic state, and M(X) is the counter cation with X being its ionic state.

Abstract: A transition metal organometallic compound comprising a transition metal in any one of group 3A to group 8 of the periodic table and cyclic compounds containing a heteroaom in group 5 or group 5B of the periodic table and having a cyclic structure including a .pi.-bonded portion and composed of said heteroatom and said .pi.-bonded portion, wherein said transition metal has a bond of a .pi.-binding heterocylic ligand, said heteroatom and said .pi.-bonded portion and a catalyst for polymerizing olefin comprising the above organic metal compound and an organic compound.

Abstract: The present invention relates to novel compounds for use as imaging agents. In particular, the present invention relates to paramagnetic metal clusters having oxygen and/or nitrogen containing ligands useful as contrast agents for magnetic resonance imaging (MRI).

Abstract: A process for preparing a dinuclear manganese complex of formula (A) ##STR1## wherein: Mn represents manganese in the III or IV oxidation state, each X is independently a co-ordinating or bridging species selected from H.sub.2 O, O.sub.2.sup.-, O.sup.2-, OH.sup.-, SH.sup.-, S.sup.2-,>S=O, Cl.sup.-, N.sub.3.sup.-, SCN.sup.-, N.sup.3-, RCOO.sup.-, NH.sub.2.sup.- and NR.sub.

Abstract: Compounds of the formula(R.sup.11 Re).sub.k O.sub.1 R.sup.12 .sub.m .multidot.L.sub.n (III)in whichR.sup.11 is a hydrocarbon group which is bonded to the rhenium via a carbon atom to which at least one hydrogen atom is still attached,R.sup.12 is aliphatic hydrocarbon radical which may contain silicon bridge atoms, or is an unsubstituted or substituted phenyl radical,L is a ligand which is bonded to the rhenium metal via one to three oxygen and/or nitrogen atoms, and theindex k is 1 or 2, the index 1 is an integer from 1 to three times k, the index m is zero or an integer from 1 to twice k, and the index n is an integer from 1 to three times k, and in which the indices k, l, m and n are selected such that their combination satisfies the 5-, 6- or 7-valence of rhenium.The invention also provides compounds of the formula(polymer).sub.f .multidot.(CH.sub.3 ReO.sub.3).sub.8 (VI)in which the rhenium compound CH.sub.3 ReO.sub.3 is bonded to the polymer via amine or amide nitrogen in the polymer.

Abstract: Manganese bromide solution for use in the formation of organomanganese compounds, applicable to the synthesis of organic products, particularly ketones.

Abstract: The invention pertains to rhenium (VII) compounds which are catalysts for metathesis of ordinary olefins (hydrocarbons) and functionalized olefins in a homogeneous phase and to methods of synthesizing these compounds. The rhenium compounds comprise a rhenium (VII) atom centrally linked to an alkylidene ligand, an alkylidyne ligand, and two other ligands of which at least one ligand is sufficiently electron withdrawing to render the rhenium atom significantly active for metathesis.

Abstract: The present invention is based on the discovery that the previously disclosed tetranuclear manganese compounds are converted into a hexadeca manganese aggregate and a core of 4 barium, 2 sodium and 1 chloride ion. Stated differently, one embodiment of the present invention comprises a composition of matter having the formula:[Mn.sub.16 Ba.sub.8 Na.sub.2 ClO.sub.4 (OH).sub.4 (CO.sub.3).sub.4 (H.sub.2 O).sub.22 L.sub.8 ].multidot.xH.sub.2 Owherein x is an integer ranging from 0 to about 32 and L is a ligand having the formula: ##STR1## Another embodiment of the present invention comprises a method of preparing the novel compounds of the present invention, which method comprises preparing an aqueous solution containing sodium chloride, a source of carbonate ion selected from sodium carbonate, sodium bicarbonate and mixtures thereof and a compound having the formula:Ba.sub.2 [Mn.sub.4 (O)(OH)(O.sub.2 CR).sub.2 L.sub.

Abstract: Transition metal cyclopentadienyl carbonyl compounds of the formula:[R.sub.x C.sub.p M(CO).sub.y ].sub.nwherein R is hydrocarbyl, C.sub.p is cyclopentadienyl, M is a transition metal, x is 0 or an integer from 1 to 5, y is an interger from 1 to 7, provided that when x is 2 to 5, R can represent two or more different hydrocarbyl groups and any two R groups can together form a fused ring with the cyclopentadienyl moiety, and n is 1 or 2,are prepared in one step by carbonylating a mixture of (i) a transition metal salt of an organic carboxylic acid a .beta.-diketone, or a .beta.-keto ester (ii) a cyclopentadiene compound (iii) and a metal alkyl reducing agent.

Abstract: A process for making ammonolytic precursors to nitride and carbonitride ceramics. Extreme reaction conditions are not required and the precursor is a powder-like substance that produces ceramics of improved purity and morphology upon pyrolysis.

Abstract: The process of this invention for preparing Mn(II) chelate comprises forming the Mn(II) chelate by mixing manganese(II) oxide (insoluble) with an aqueous suspension comprising a molar equivalent or molar excess of the insoluble protonated chelating compound at a temperature of from 20.degree. to 50.degree. C. When the reaction is carried out with a protonated chelating agent in the absence of base, a precipitate of the protonated Mn(II) chelate is formed. A low osmolarity Mn(II) chelate solution can be formed from the precipitates by dissolving them in an aqueous solution of base. When the initial chelate forming reaction is carried out in a solution containing a molar equivalent or excess of sodium hydroxide, a low osmolarity solution of the Mn(II) chelate is directly formed with most chelating agents. Preferred chelating compounds for this process include DPDP, DTPA, DCTA, EDTP, DOTA, DOXA, DO3A and EDTA.

Abstract: The invention relates to a process for the preparation of compounds of formula Ia[R.sup.1 FeR.sup.2' ].sup..sym..sub.q [LQ.sub.m ].sup.q.crclbar.(Ia),wherein R.sup.1 is a .pi.-arene, R.sup.2' is an anion of a .pi.-arene, L is a divalent to heptavalent metal or non-metal, Q is a halogen atom, q is an integer from 1 to 3 and m is an integer corresponding to the valency of L+q, said process comprises reacting an uncharged .pi.-complex of the formula IIIa[(R.sup.2').sub.2 Fe] (IIIa)with a .pi.arene R.sup.1 is in the presence of Al and a Lewis-acid followed by treatment with an acid or a salt of an acid of the anion [LQ.sub.m ].sup.q-, the improvement consisting essentially of using TiCl.sub.4 as a Lewis-acid.

Abstract: The invention describes a helicene compound having the structure ##SPC1##which contains seven six-membered conjugated aromatic rings capped by two five-membered rings which do not superimpose on each other.The invention also describes a helical metallocene oligomer capped by unsaturated five-membered rings, having the structure: ##SPC2##wherein M is a transition metal halide and n=1 to 100.Method for the preparation of these compounds are also presented.

Abstract: A process for making ammonolytic precursors to nitride and carbonitride ceramics. Extreme reaction conditions are not required and the precursor is a powder-like substance that produces ceramics of improved purity and morphology upon pyrolysis.