Abstract: An alkali metal- or alkali earth metal-containing organic compound (i) is reacted with a leaving group- and silicon- or germanium-containing compound (ii) in the presence of a nitrogen-containing aromatic heterocyclic compound. By such a method, it is possible to produce a silicon- or germanium-containing organic compound, for example, a cyclopentadienyl compound cross-linked by a silicon atom or a germanium atom, typically a cyclopentadienyl compound which is substituted with a substituted or unsubstituted silyl or germyl group, for a short time with a high yield.

Abstract: Novel heterogeneous catalysts for the which hydrogenation of olefins and arenes with high conversion rates under ambient conditions and the polymerization of olefins have been developed. The catalysts are synthesized from Ziegler-type precatalysts by supporting them on sulfate-modified zirconia.

Abstract: A cyclopentadienyl metal salt is prepared by reacting a cyclopentadiene and a metal hydride in the presence of an amine compound. Furthermore, a derivative of a cyclopentadiene in which a phenyl group is bonded to its cyclopentadienyl moiety through an element of the 14 group of the Periodic Table is prepared using such a reaction.

Abstract: Disclosed herein are polysilole and polygermole compounds. The silicon or germanium ring atom is directly linked in the polymer to another silicon or germanium ring atom from another polymer unit. The result is compounds that fluoresce and have electroluminescence. Coupling reactions to form such compounds are also disclosed.

Abstract: This invention provides: (a) new organotin functionalized silanes: (b) a solid prepared by chemically bonding organotin functionalized silanes to a solid inorganic support containing surface hydroxy groups: (c) a solid catalyst prepared from said supported organotin functionalized silane; (d) a process for conducting esterification or transesterification, and urethane, urea, silicone, and amino forming reaction utilizing said solid supported catalyst; (e) a process of separating the solid supported catalyst from the reaction products employing ligand-solid separation techniques; (f) reuse of the solid supported catalyst after being separated from the reaction products; (g) a continuous esterification or transesterification reaction or urethane, urea, silicone, or amino form.

Abstract: Novel tripodal cyclopentadiene derivatives have the formula (I) ##STR1## where E are identical or different and are --N(R)(R), --P(R)(R), --As(R)(R), --Sb(R)(R), --OR, --SR, --SeR, --TeR, where R are identical or different and are each hydrogen, a C.sub.1 -C.sub.20 -carboorganic radical or a C.sub.1 -C.sub.30 -organosilicon radical, or E is a leaving group X andR.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6 are identical or different and are each hydrogen, a C.sub.1 -C.sub.20 -carboorganic radical or a C.sub.1 -C.sub.30 -organosilicon radical,Z is a cyclopentadienyl radical or a substituted cyclopentadienyl structural unit andT is hydrogen, a C.sub.1 -C.sub.20 -carboorganic radical or a C.sub.1 -C.sub.30 -organosilicon radical or a group E--Y--, where E is --N(R)(R), --P(R)(R), --As(R)(R), --Sb(R)(R), --OR, --SR, --SeR, --TeR or a leaving group X, where R are identical or different and are each hydrogen, a C.sub.1 -C.sub.20 -carboorganic radical or a C.sub.1 -C.sub.

Abstract: A process for preparing bis-cyclopentadienyl compounds bridged by a methylene group is reported, said process comprising reacting formaldehyde with a cyclopentadienyl compound in the presence of a base and of a solvent having a dielectric constant (.epsilon.), measured at 25.degree. C., higher than 7. The bridged compounds, obtainable in high yields with this simple single-step process, can be used to prepare ansa-metallocenes, active as catalyst components in the polymerization of olefins.

Abstract: The present invention provides several methods of synthesis and separation in which organic/fluorous phase separation techniques are used to effect separations. The present invention also provides novel compositions of matter comprising fluorous Si, Sn and Ge compounds.

Abstract: This invention relates to a multifunctional organic alkali metal initiator for the preparation of various kinds of star polymers by anionic polymerization, a process for making the initiator, a process using said initiator for making star polymers and the polymers obtained. The initiator can be represented by the formula: M.sub.a (RMe).sub.b, wherein M is selected from Sn, Ti, Al, Si and/or B; R is a hydrocarbyl group containing 8-100 carbon atoms, a=1-3, b=2.5-6.5, Me is an alkali metal which may be selected from Na and Li. The initiator was synthesized by reacting an organic alkali metal with a conjugated diene and/or a mono-olefin monomer, and then adding hetero-atom containing halide. The star polymer obtained has a radial molecular structure consisting of several macromolecular chain arms radiating from the initiator core, and its molecular weight distribution expressed by GPC presents a uniform singlet.

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: Amyloid binding compounds which are non-azo derivatives of Chrysamine G, pharmaceutical compositions containing, and methods using such compounds to identify Alzheimer's brain in vivo and to diagnose other pathological conditions characterized by amyloidosis, such as Down's Syndrome are described. Pharmaceutical compositions containing non-azo derivatives of Chrysamine G and methods using such compositions to prevent cell degeneration and amyloid-induced toxicity in amyloidosis associated conditions are also described. Methods using non-azo Chrysamine G derivatives to stain or detect amyloid deposits in biopsy or post-mortem tissue are also described. Methods using non-azo Chrysamine G derivatives to quantify amyloid deposits in homogenates of biopsy and post-mortem tissue are also described.

Abstract: The present invention relates to a process for synthesizing novel intermediates of formula III: ##STR1## wherein R.sup.1 is a halogen. The intermediate compounds described herein are useful for the preparation of carbapenem compounds.

Abstract: A very effective catalyst system for the polymerization or copolymerization of olefins comprises a cocatalyst, preferably an aluminoxane or a supported aluminoxane, and a metallocene of the formula I ##STR1## in which, in the preferred form, M.sup.1 in Zr or Hf, R.sup.1 and R.sup.2 are halogen or alkyl, R.sup.3 is alkyl, R.sup.4 to R.sup.12 are alkyl or hydrogen and R.sup.13 is a (substituted) alkylene or heteroatom bridge. The metallocenes, in particular the zirconocenes, produce polymers of very high molecular weight, in the case of prochiral monomers polymers of very high molecular weight, very high stereotacticity and very high melting point, at high catalyst activities in the industrially particularly interesting temperature range between 50 and 80.degree. C. In addition, reactor deposits are avoided by means of supported catalyst systems.

Abstract: The present invention provides a catalyst for transesterification comprising an organotin compound expressed by the following general formula (I): ##STR1## wherein, X, Y, and Z represent, respectively and independently, an alkoxyl group, alkylthio group, halogen atom, or alkyl group; where at least two groups among X, Y, and Z represent an alkoxyl group, alkylthio group, or halogen atom; R represents an organic chain; and R' represents a hydrogen atom, or alkyl group.

Abstract: The invention relates to a organo-tin-containing complex stabilizer for synthetic resin compositions of the formula I:M.sup.2+.sub.1-a-b(2+x) Al.sup.3+.sub.a [Sn(R).sub.(2-x) ].sub.b.sup.(2+x)+ (OH).sup.-.sub.2-b(2+x) A.sup.n-.sub.a/n *mH.sub.2 O (I)wherein M.sup.2+ stands for at least one divalent metal cation, R stands for a C.sub.1-12 linear or branched alkyl group, A.sup.n- stands for an n-valent anion or mixtures of anions, and the following conditions apply:0<a<0.5; 0<b<0.1; 0.ltoreq.x.ltoreq.1; 0<a+b(2+x)<0.5; 0.ltoreq.m.ltoreq.2.The invention also relates to a method for the preparation of these stabilizers and their use in synthetic resin compositions, preferably halogen-containing synthetic resin compositions, or (co)polymers obtained by Ziegler Natta polymerization processes.

Abstract: The present invention relates to a process for preparing racemic ansa-metallocene complexes I ##STR1## tin compounds II ##STR2## and a process for preparing tin compounds II. R.sup.1 to R.sup.9, M, and X are defined herein.

Abstract: Triorgano substituted-tin lithium initiators are made in a dimethyl ether solvent. The substitution of dimethyl ether as the solvent for the traditional tetrahydrofuran solvent results in an initiator for anionic polymerizations that can produce less 1,2-vinyl repeat units. The dimethyl ether is also easier to remove from the polymerization media because it has a boiling point at one atmosphere of minus 24.8.degree. C. and thus is a gas at 25.degree. C.

Abstract: A catalyst precursor of the formula: ##STR1## wherein: R.sup.1 is a cycloalkadienyl ligand;R.sup.2, R.sup.3, R.sup.4, and R.sup.5 are independently hydrogen, a hydrocarbyl group containing 1 to 20 carbon atoms, or a silyl group, and may be connected to R.sup.1 through a bridging group comprising at least two Group IVA atoms; with the proviso that one of R.sup.3, R.sup.4, and R.sup.5 is a negative charge stabilizing group selected from the group consisting of Group IVA trialkyl groups, aryl groups, heteroaromatic groups, ethylenically unsaturated hydrocarbon groups, acetylenically unsaturated hydrocarbon groups, ketonic groups, and aromatic organometallic moieties, is provided. When combined with a compound comprising a metal from Groups IIIB to VIII or the Lanthanide series of the Periodic Table of elements and an activating cocatalyst, the catalyst precursor is useful for the polymerization of olefins.

Abstract: A compound and method for controlling Take-all disease of plants are disclosed by applying a fungicide of the formula: ##STR1## wherein Z.sub.1 and Z.sub.2 are carbons of a benzene ring; A is selected from the group consisting of --C(X)-amine wherein the amine is substituted with a first and a second amine substituent or with an alkylaminocarbonyl and a hydrogen, --C(O)--SR.sub.3, --NH--C(X)R.sub.4, and --C(.dbd.NR.sub.3)--XR.sub.7 ;B is --W.sub.m --Q(R.sub.2).sub.3 ; Q is Si, Ge, or Sn; W is --C(R.sub.3).sub.p H.sub.(2-p) --; n is 0, 1, 2, or 3; m is 0 or 1; p is 0, 1, or 2;or an agronomic salt thereof;the first and second amine substituents and R, R.sub.2, R.sub.3, R.sub.4, and R.sub.7 are defined herein.

Abstract: A process for preparing metallocene complexes of the general ##STR1## in which the substituents have the following meanings:M is titanium, zirconium, hafnium, vanadium, niobium or tantalum,X is fluorine, chlorine, bromine, iodine, hydrogen, C.sub.1 -C.sub.10 -alkyl, C.sub.6 -C.sub.15 -aryl or --OR.sup.5,where R.sup.5 is C.sub.1 -C.sub.10 -alkyl, C.sub.6 -C.sub.15 -aryl, alkylaryl, aryl-alkyl, fluoroalkyl or fluoroaryl with, in each case, 1 to 10 carbon atoms in the alkyl radical and 6 to 20 carbon atoms in the aryl radical,R.sup.1 to R.sup.4 and R.sup.6 to R.sup.9 are hydrogen, C.sub.1 -C.sub.10 -alkyl, 5- to 7-membered cycloalkyl which can in turn carry C.sub.1 -C.sub.10 -alkyls as substituents, or C.sub.6 -C.sub.15 -aryl or aryl-alkyl, it also being possible where appropriate for two adjacent radicals together to be cyclic groups having 4 to 15 carbon atoms, or Si(R.sup.10).sub.3 withR.sup.10 being C.sub.1 -C.sub.10 -alkyl, C.sub.6 -C.sub.15 -aryl or C.sub.3 -C.sub.

Abstract: Disclosed are monovinyltin trihalides of he general formula (I):(x)(x.sup.1)(x.sup.2)Sn--C(R).dbd.C(R.sup.1)--C(O)--R.sup.2(I)and a process for their preparation from 1,3-diketones, tin(II) halides and halogen acids.

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: The present invention provides a method for carrying out a chemical reaction comprising the steps of forming an organic/fluorous solubilizing liquid phase comprising a solvent system. The solvent system is selected or adapted to substantially solubilize a fluorous reaction component or components (that is, a fluorous reagent, a fluorous catalyst and/or a fluorous reactant). The "fluorous reaction component" is functionalized to comprise at least one fluorous moiety having the formula -(R).sub.d (Rf).sub.e. (Rf).sub.e is at least one fluorous group and e is a whole number. (R).sub.d is an organic (for example, hydrocarbon) spacer group, which may be present or absent, and d is an integer equal to at least zero. The solvent system is also adapted to substantially solubilize an organic reaction component or components. After the reaction occurs in the organic/fluorous solubilizing liquid phase, a phase separation into at least a fluorous phase and an organic phase is effected.

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 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: 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 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: The invention relates to new transition metal compounds useful as olefin polymerization catalysts. They are characterized by the formula (V)(E)(W)M(L), which in which M is a transition metal, V, E, and W, is e.g.

Abstract: A metallocene catalyst system for the polymerization of .alpha.-olefins to yield stereospecific polymers including syndiotactic, and isotactic polymers. The catalyst system includes a metal and a ligand of the formula ##STR1## wherein: R.sup.1, R.sup.2, and R.sup.3 are independently selected from the group consisting of hydrogen, C.sub.1 to C.sub.10 alkyl, 5 to 7 membered cycloalkyl, which in turn may have from 1 to 3 C.sub.1 to C.sub.10 alkyls as a substituent, C.sub.6 to C.sub.15 aryl or arylalkyl in which two adjacent radicals may together stand for cyclic groups having 4 to 15 carbon atoms which in turn may be substituted, or Si(R.sup.8).sub.3 where R.sup.8 is selected from the group consisting of C.sub.1 to C.sub.10 alkyl, C.sub.6 to C.sub.15 aryl or C.sub.3 to C.sub.10 cycloalkyl; R.sup.4 and R.sup.6 are substituents both having van der Waals radii larger than the van der Waals radii of groups R.sup.1 and R.sup.3 ; R.sup.

Abstract: The quaternary Zintl material (Et.sub.4 N).sub.4 ?Au(Ag.sub.1-x Au.sub.x).sub.2 Sn.sub.2 Te.sub.9 ! that contains 1-D semiconducting chains composed of four metallic elements is prepared by treating ethylenediamine extracts of a pentanary K--Au--Ag--Sn--Te alloy with Et.sub.4 NI.

Abstract: Intermediate compounds represented as formula (I) useful for the synthesis of 16-phenoxy-prostatrienoic acid derivatives and a preparing method thereof are disclosed. ##STR1## wherein R is tetrahydropyranyl, tetrahydrofuranyl, 2-ethoxyethyl, t-butyldimethylsilyl, triisopropylsilyl or triethylsilyl group; R.sup.1 and R.sup.2 are independently hydrogen or ester-forming group; P is hydrogen, trimethylsilyl or tri-n-butyltin; and wavy line means epi-stereoisomeric mixture.

Abstract: A synthetic method for generating pure carboxyethyl germanium sesquioxide in the absence of toxic impurities. In the method germanium dioxide and metallic germanium are not used as starting materials. The method involves steps which ensure (a) absence of any residual germanium tetrachloride to ensure none is available to form germanium dioxide, (b) removal of any germanium dioxide, (c) removal of any germanium tetrachloride later produced from any germanium dioxide and (d) final removal of any germanium dioxide. In an alternative method, intermediate TPA is prepared by direct precipitation from a concentrated solution with a halogenated solvent preferably dichloromethane when poured into a non-polar alkyl solvent preferably hexane at ambient temperature and then converted to carboxyethyl germanium sesquioxide.

Abstract: Cyclopentadineyl compounds of the formula II ##STR1## and formula III ##STR2## their preparation and their use as intermediates in the preparation of metallocene complexes of the formula I.

Abstract: The present invention relates to novel reaction products of azlactones and organometallic nucleophiles and the method of making these reaction products. The invention also relates to methods of using such reaction products to prevent or eliminate microbial and fungal growth on substrates. Reaction products can be provided that show improved antifouling and antimicrobial action.

Abstract: Metallocene complexes of the general formula I ##STR1## where the substituents Y, M, x, R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.6, R.sup.7, R.sup.8, and R.sup.9 are as described in the disclosure, and ligand systems of the general formula II ##STR2## as intermediates.

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: A process for making a metallocene, said process comprising the steps of (a) reacting an alkylsubstituted cyclopentadiene ligand, which contains a mixture of endo- and exo-isomers, with up to about a 10% excess over a stoichiometric amount of a deprotonation agent based on the amount of endo-isomers, so as to form a salt of said endo-isomers, (b) reacting the endo-isomer salt with a transition or actinide metal compound so as to form said metallocene and (c) optionally separating said exo-isomers and trace amounts of unreacted endo-isomers from said metallocene by distillation.

Abstract: A synthetic method for generating pure carboxyethyl germanium sesquioxide in the absence of toxic impurities. In the method germanium dioxide and metallic germanium are not used as starting materials. The method involves steps which ensure (a) full reaction of germanium tetrachloride to ensure none is available to form germanium dioxide, (b) removal of any germanium dioxide, (c) removal of any germanium tetrachloride later produced from any germanium dioxide and (d) final removal of any germanium dioxide.

Abstract: The invention relates to new bridged organotin compounds useful in preparing bridged stereorigid metallocenes via organomagnesium and organotin compounds.

Abstract: Processes are disclosed for preparing compounds of the formula Z--R--Z where each Z can be selected from cyclopentadienyl type radicals such as substituted or unsubstituted cyclopentadienyl, indenyl, fluorenyl or tetrahydroindenyl or where one Z is Cl, Br, or I by reacting specific Z precursors with a dihaloalkylene compound. Also new cyclopentadienyl-type compounds are disclosed.

Abstract: Disclosed are: a vinyl-substituted benzylorganotin compound represented by the following general formula A: ##STR1## wherein R.sup.1 R.sup.2 C.dbd.CR.sup.3 --, R.sup.4, R.sup.5, R.sup.6 and R.sup.7 are each a group bonded to the benzene ring and R.sup.1 to R.sup.7 are each one of a hydrogen atom and a hydrocarbon group having 1 to 30 carbon atoms which is one of aliphatic, alicyclic and aromatic hydrocarbon groups, R.sup.8 to R.sup.10 are each a hydrocarbon group having 1 to 30 carbon atoms which is one of aliphatic, alicyclic and aromatic hydrocarbon groups and R.sup.1 to R.sup.

Abstract: A highly effective catalyst system for the polymerization of olefins comprises a cocatalyst, preferably an aluminoxane, and a metallocene of the formula I ##STR1## where M.sup.1 =Zr or Hf, R.sup.1 and R.sup.2 =(C.sub.1 -C.sub.4)-alkyl or chlorine, R.sup.3, with the proviso that at least one of the radicals R.sup.3 is not hydrogen, =hydrogen, F, Cl, --OR.sup.7, --NR.sup.7 R.sup.8, --P(O)R.sup.7 R.sup.8, --P(OR.sup.7).sub.2 or SR.sup.7, R.sup.4 is a ##STR2## radical, and m plus n are zero or 1.

Abstract: Solutions of triorganotin lithium are described having low residual concentrations (preferably less than 2,000 ppm) of halide. These are produced by a two-step process.Triorganotin halide is reacted with lithium to produce hexaorgano ditin and a precipitate of lithium halide. The lithium halide precipitate is removed by filtration and/or use of highly concentrated reaction conditions. Then the hexaorgano ditin is further reacted with lithium to form the triorgano substituted tin lithium. The lithium halide is less soluble in hot tetrahydrofuran (THF) and/or more concentrated solutions. THF is a preferred solvent for the reaction. The low-temperature reactions described result in low amounts of inactive and/or undesirable byproducts. These triorganotin lithium compounds are useful as anionic initiators that result in polymers with terminal tin compounds, e.g., triorganotin, attached to the terminal end of the polymer where initiation occurred.

Abstract: The magnesium complexes of cyclic hydrocarbons containing conjugated dienes, such as 1,2-dimethylenecycloalkanes, and 1,3-butadienes, are readily prepared in high yields using highly reactive magnesium. Reactions of these (2-butene-1,4 diyl)magnesium reagents with electrophiles such as dibromoalkanes, alkylditosylates, alkylditriflates, bromoalkylnitriles, esters, or amides serve as a convenient method for synthesizing carbocyclic systems. Significantly, carbocycles prepared by this method contain functional groups such as the exocyclic double bond or a keto group in one of the rings which could be used for further elaboration of these molecules. Furthermore, fused bicyclic systems containing a substituted five-membered ring can be conveniently prepared at high temperatures by the reactions of (2-butene-1,4-diyl)magnesium complexes with carboxylic esters or acid halides whereas low temperatures lead to regioselective synthesis of .beta.,.gamma.-unsaturated ketones. Additionally, .gamma.

Abstract: A catalyst component for use in the polymerization of .alpha.-olefins, comprising a compound represented by the following general formula [I]: ##STR1## wherein R.sup.1 s represent a hydrogen atom, a C.sub.1-6 hydrocarbon group or a C.sub.1-12 hydrocarbon group containing silicon; each of R.sup.2 and R.sup.3 independently represents a divalent group selected from the group consisting of a hydrocarbon group having 3 to 30 carbon atoms and a silicon-containing hydrocarbon group having 1 to 30 carbon atoms and 1 to 6 silicon atoms, provided that at least one of R.sup.2 and R.sup.3 is said silicon-containing hydrocarbon group; Q represents a C.sub.1-20 divalent hydrocarbon group, a silylene group, a silylene group with a C.sub.1-20 hydrocarbon group, a germylene group, or a germylene group with a C.sub.1-20 hydrocarbon group; X and Y represent H, a halogen, a C.sub.1-20 hydrocarbon group, or a C.sub.

Abstract: A method for preparing 1,4-(Z,Z)-disubstituted-1,4-disulfurated-1,3-butadienes is disclosed. The butadienes can be further elaborated to provide 3,6-unsymmetrically-substituted-1,2-dithiins. Also disclosed are butadienes prepared by the method of the invention. These butadienes are useful as intermediates in the synthesis of antibiotic 1,2-dithiins.

Abstract: Process for the preparation of an olefin polymer using metallocenes containing specifically substituted indenyl ligandsA highly effective catalyst system for the polymerization of olefins comprises a cocatalyst, preferably an aluminoxane, and a metallocene of the formula I ##STR1## in which, preferably M.sup.1 is Zr or Hf, R.sup.1 and R.sup.2 are alkyl or halogen, R.sup.5 is hydrogen or alkyl, R.sup.3 and R.sup.4 are alkyl, where R.sup.3, R.sup.4 and R.sup.5 may be halogenated, --(CR.sup.7 R.sup.8).sub.m --R.sup.6 --(CR.sup.7 R.sup.8).sub.n -- is a single- or multi-membered chain in which R.sup.6 may also be a (substituted) heteroatom, and m+n is zero or 1.

Abstract: A protected 6-trimethylstannyl dopa derivative has been synthesized for the as a precursor for the preparation of 6-[.sup.18 F]fluoro-L-dopa. The tin derivative readily reacts with electrophilic radiofluorinating agents such as [.sup.18 F]F.sub.2, [.sup.18 F]OF.sub.2 and [.sup.18 F]AcOF. The [.sup.18 F]fluoro intermediate was easily hydrolyzed with HBr and the product 6-[.sup.18 F]fluoro-L-dopa was isolated after HPLC purification in a maximum radiochemical yield of 23%, ready for human use.

Abstract: A process for the preparation of a compound of the formula III ##STR1## comprising, deprotonating a solution or suspension of an indene of the formula I ##STR2## in a solvent or solvent mixture containing a base to give a suspension of a metallated product of the compound of formula I, adding to the suspension of the metallated product a compound of the formula IIX--R.sup.6 --X (II)and reacting the suspension of the metallated product and compound of the formula II.