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In preparation for the Memorial Day Weekend, Grand Canyon National Park would like to remind everyone to be fire aware and “know before you go” to your public lands

Although Grand Canyon National Park received below-average precipitation this winter, the warm spring caused vegetation in the park to thrive. Now, fine fuels are quickly drying out as winds and temperatures rise, increasing the risk of wildfire. https://www.nps.gov/grca/learn/news/memorial-day-fire-aware.htm




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Process for the preparation of O-desmethyl venlafaxine and intermediate for use therein

The present invention relates to a compound of formula A, wherein R is alkyl. Compound A may be used as an intermediate in the preparation of O-desmethyl venlafaxine or a salt thereof, and the present invention provides such a preparation, as well as a process for preparing the compound of formula A.




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Method for preparation of aryl poly(oxalkyl) quaternary ammonium compound

A method for preparation of an aryl poly(oxalkyl) quaternary ammonium compound is provided, said method comprising steps of: 1) reacting a phenol with a dihalopolyalkylene ether under the action of a phase transfer catalyst, to obtain an arylpoly(oxalkyl) halide; 2) reacting said arylpoly(oxalkyl) halide with an amination reagent under the action of a phase transfer catalyst, to obtain an arylpoly(oxalkyl) amine; 3) reacting said arylpoly(oxalkyl) amine with an alkylation reagent, to obtain an aryl poly(oxalkyl) quaternary ammonium compound; wherein R1 is H or a C1 to C16 alkyl group, located in the ortho, meta or para position; n is an integer of 2 to 6; R2 is H or a C1 to C16 alkyl group; R3 is H or a C1 to C16 alkyl group; R4 is a C1 to C16 alkyl group; X1 is Br or Cl; X is Cl, Br, or I. The preparation method according to the present invention requires low temperature and low pressure, the reaction time is short, and an overall yield can reach 75%. The operation is simple, the cost is low, and the product can be separated easily and have a purity of pharmaceutical grade, thereby facilitating the large-scale production.




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Process for the preparation of crystalline forms of agomelatine and novel polymorph thereof

The invention concerns a new process for the preparation of crystalline form of agomelatine from a solution of agomelatine in a solvent, characterized in that the agomelatine is crystallized by instantaneous precipitation from said solution, at a temperature equal to or below −10° C.




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Ceramide dimers and use thereof as pharmaceutical preparation or cosmetic preparation

The invention relates to ceramide dimers which are constructed from two ceramide molecules which are crosslinked to each other via their lipophilic end. The ceramide molecules thereby have at least one hydrophilic group at their hydrophilic end for increasing the hydration shell of the dimer. The ceramide dimers according to the invention can be used as pharmaceutical preparation or as cosmetic preparation.




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Process for the preparation of fatty acid alkyl esters (biodiesel) from triglyceride oils using eco-friendly solid base catalysts

This invention relates to an improved process for the preparation of green fatty acid methyl esters (FAME; commonly called as biodiesel) from different triglyceride oils using mixed metal oxides derived from layered double hydroxides (referred here as LDHs) as reusable solid heterogeneous base catalysts. This process uses very low alcohohoil molar ratio and catalyst and/or products are easily separable after the reaction through simple physical processes. The properties of thus obtained biodiesel meet the standard biodiesel values and can directly be used as transport fuel.




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Process for the preparation of chiral triazolones

A process for the preparation of a chiral compound, in particular posaconazole, wherein the process comprises mixing and reacting the compounds of formula (I) Y3—NH2; of formula (IIa) 0=C═N—Y0 and/or of formula (IIb) and of formula (III) in a solvent in any order to obtain a reaction mixture containing a chiral compound of formula (IV) and/or formula (V).




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Novel 6-acyl-(6H)-dibenz[c,e][1,2]oxaphosphorin 6-oxides, their preparation and their use as photoinitiators

The invention relates 6-acyl-(6H)-dibenz[c,e][1,2]oxaphosphorin-6-oxides of the formula ##STR1## wherein each of R1, R2 and R3 may be present one or more times and R1, R2 and R3 represent halogen having an atomic number of from 9 to 35, alkyl or alkoxy each having from 1 to 6 carbon atoms and wherein Ar represents an aromatic hydrocarbon group having from 6 to 10 carbon atoms.The invention further relates to a process for the preparation of the afore-mentioned compounds and polymerizable compositions containing them as an essential ingredient as a photo-initiator. Finally the invention relates to 6-alkoxy-(6H)-dibenz[c,e][1,2]oxaphosphorin of the formula II ##STR2## wherein each of R1 and R2 may be present once or more times and R1 and R2 represent halogen having an atomic number of from 9 to 35, alkyl or alkoxy each having from 1 to 6 carbon atoms, at least one R1 being, however, halogen and wherein R4 represents alkyl having from 1 to 6 carbon atoms.




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Process for the preparation of oligonucleotides

The invention relates to a process for the preparation of oligonucleotides by the following steps: reaction of a nucleoside with a phosphine derivative, reaction of the nucleotide derivative thus obtained with a nucleoside bonded to a polymeric carrier, oxidation of the carrier-bound nucleoside-nucleotide thus obtained with formation of phosphotriester groups, blocking of free primary 5'--OH groups, elimination of a protective group from the terminal 5'--OH group, where appropriate single or multiple repetition of the abovementioned steps to introduce further nucleoside phosphate or oligonucleoside phosphate units, and cleavage of the nucleoside-carrier bond and, where appropriate, elimination of all protective groups present in the oligonucleoside phosphates. The phosphine derivative used is a compound of the general formula III ##STR1## in which X and L can react with OH groups of the sugar units in the oligonucleotides, and R3 is a protective group which can be liberated by β-elimination.




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Derivatives of purine, process for their preparation and a pharmaceutical preparation

Antivirally active compounds of formula (I), wherein R1 is hydrogen, hydroxy, mercapto or amino; R2 is hydrogen, hydroxy, fluoro, chloro or amino; R3 and R4 are independently selected from (II), (III), amino, hydroxy or an ether or ester residue thereof, or R3 together with R4 is (IV), wherein M is hydrogen or a pharmaceutically acceptable counterion; and n is 1 or 2; with the proviso that, when R2 is amino and R3 and R4 are hydroxy, R1 is not hydroxy and in addition, when n=1, R1 is not hydrogen, and pharmaceutically acceptable salts thereof; processes for preparation of said compounds, a pharmaceutical composition comprising said compounds, methods for treatments of virus infections as well as use of compounds of formula (I) without the proviso for the manufacture of a medicament for treatment of AIDS. ##STR1##




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Bridged bis-fluorenyl metallocenes, process for the preparation thereof and use thereof in catalysts for the polymerization of olefins

Metallocene compounds having two fluorenyl ligands bridged with a single silicon or germanium atom, said atom having two substituent groups containing a total of at least four carbon atoms, are useful as catalyst components for the polymerization of olefins. Particularly, it is possible to prepare high molecular weight atactic polypropylene with improved yields with respect to the known catalysts.




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Diene complexes of group 4 metals and process of preparation

Disclosed is a process for preparing bridged Group 4 metal complexes containing a neutral diene ligand starting from the corresponding novel, metal diene containing complexes by reaction thereof with the divalent derivative of a bridged bidentate ligand compound. The novel, intermediate metal diene complexes, their formation from tetravalent metal salts and an integrated process combining both process steps are claimed.




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Preparation of addition polymerization catalysts

Metal complexes useful as components of addition polymerization catalysts are prepared by oxidizing Group 4 or Lanthanide metal containing complexes using an organic halide oxidizing agent in a unique one electron oxidation.




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Metallocene compounds, processes for the preparation thereof, catalyst components for olefin polymerization, and processes for the production of olefin polymers

A metallocene compound is provided wherein to a transition metal compound is bonded a multidentate compound wherein a substituted cycloalkadienyl ring CA1 having therein a heteroaromatic group Ra containing an oxygen, sulfur or nitrogen atom on a cycloalkadienyl ring, preferably the five-membered ring thereof, and an unsubstituted or substituted cycloalkadienyl group CA2 or --(R1)N--, --O--, --S-- or --(R1)P--, preferably CA2, more preferably a substituted cycloalkadienyl group identical with CA1 are bonded through a divalent linking group. The metallocene compound is suitable as a principal ingredient of a catalyst for the polymerization of olefins, particularly achieving a very high effect in making the molecular weight of a polypropylene higher.




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Process for the preparation of polyether phosphates

The invention provides an improved process for the synthesis of compounds carrying at least one phosphate group, especially polyalkylene glycol phosphate compounds, said process comprising the steps of: (a) reacting a compound containing at least one primary alcohol moiety with a diaryl- or diaralkyl-halophosphate whereby to form the corresponding diaryl- or diaralkyl-phosphate ester; (b) reductively cleaving the resulting product; and (c) if desired, repeating steps (a) and (b) with the product of step (b) whereby to produce a compound carrying two or more phosphate groups. Advantages of the process in accordance with the invention are that this avoids the production of by-products and results in products which are low in impurities. Also provided are novel diaryl- and diaralkyl-phosphate ester compounds, in particular polyethylene glycol diphenylphosphate ester and derivatives thereof.




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Preparation of triethyl phosphate

The invention relates to a process for preparing triethyl phosphate by reacting phosphorus oxychloride with a greater than stoichiometric quantity of ethanol under reduced pressure at temperatures of from 0 to 50° C. in a reaction vessel, wherein a) the volatile components resulting from the reaction are predominantly condensed by means of a reflux condenser and the remaining volatile components are passed into a scrubber filled with water,b) after the end of the reaction, the reaction mixture is separated distillatively in an outgassing column into a top product and a bottom product which predominantly comprises triethyl phosphate,c) the top product of the outgassing column is combined with the contents of the scrubber andd) the contents of the scrubber are separated distillatively in an azeotropic distillation to obtain water and ethanol as top product and the ethanol, preferably after dewatering, is preferably returned to the reaction.




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Preparation of silicon-bridged metallocene compounds

A process for obtaining silicon-bridged metallocene compounds comprising the following steps: a) reacting, at a temperature of between −10° C. and 70° C., the starting ligand with about 2 molar equivalents of an alkylating agent;b) after the reaction has been completed, adding at least 2 molar equivalents of an alkylating agent that can be also different from the first one; andc) reacting, at a temperature of between −10° C. and 70° C., the product obtained from step b) with at least 1 molar equivalent of a compound of formula ML's, wherein M is a transition metal; s is an integer corresponding to the oxidation state of the metal; and L' is an halogen atom selected from chlorine, bromine and iodine.




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Glass for magnetic recording media substrates, magnetic recording media substrates, magnetic recording media and method for preparation thereof

A glass for a magnetic recording medium substrate permitting the realization of a magnetic recording medium substrate affording good chemical durability and having an extremely flat surface, a magnetic recording medium substrate comprised of this glass, a magnetic recording medium equipped with this substrate, and methods of manufacturing the same. The glass is an oxide glass not including As or F.




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Dielectric composition and preparation method thereof

There are provided a dielectric composition and a preparation method thereof, the dielectric composition including: a first perovskite powder for a core represented by ABO3: and a second perovskite powder for a shell represented by ABO3, having an average particle diameter corresponding to ⅓ to 1/10 of an average particle diameter of the first perovskite powder, and included in an amount of 1 to 70 parts by weight with respect to 100 parts by weight of the first perovskite powder, wherein particles of the second perovskite powder have pores having a volume fraction of 3 to 50 vol % therein. According to the present invention, there are provided a dielectric composition having excellent dielectric characteristics and electrical characteristics, and a preparation method thereof.




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Ink-jet ink for color filter and method for preparing the same and method for preparation of color filter

The disclosure provides an ink jet ink for color filter and a method for preparing the same, as well as a method for preparing of a color filter. The ink jet ink for color filter comprising, by weight, 10 to 50 parts of aqueous nano pigment dispersion and 51 to 95 parts of a cold curing component.




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Crosslinkable curing super-branched polyester and cured product and preparation method thereof

A crosslinkable curing super-branched polyester and the cured product and the preparation method thereof are disclosed. The super-branched polyester has high refractive index and comprises a compound represented by the following structural formula (I). In the formula (I), HBP is the backbone of the super-branched polyester; both a and b are positive integers; the sum of a and b is less than or equal to n; n is more than or equal to 10 and less than 80. In the super-branched polyester, A is represented by formula (II) and N is represented by formula (III), wherein R is methyl or hydrogen atom; the mole ratio of N relative to the total mole of A and N is more than 30 mol %, and the ratio of the total mole of A and N relative to the product of the total mole of HBP backbone and n is more than 0.5 and less than or equal to 1.




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Ultra fast process for the preparation of polymer nanoparticles

A process for the preparation of polymer lattices comprising polymer nanoparticles by a photo-initiated heterophase polymerization includes preparing a heterophase medium comprising a dispersed phase and a continuous phase and at least one of at least one surfactant, at least one photoinitiator, and at least one polymerizable monomer. The at least one polymerizable monomer is polymerized by irradiating the heterophase medium with electromagnetic radiation so as to induce a generation of radicals. The at least one photoinitiator is selected from compounds comprising at least one phosphorous oxide group (P═O) or at least one phosphorous sulfide (P═S) group. The irradiating of the heterophase medium is effected so that a ratio of an irradiated surface of the heterophase medium to a volume of the heterophase medium is at least 200 m−1.




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Fluorographene and preparation method thereof

A fluorographene and preparation method thereof are provided. For the said fluorographene, the fraction of F is 0.5




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Process for the preparation of dichlorofulvene

The invention relates to a process for the preparation of formula (I) which process comprises pyrolyzing a compound of formula (II) wherein X is chloro or bromo, and to compounds which may be used as intermediates for the manufacture of the compound of formula I and to the preparation of said intermediates.




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Process for the preparation of fluoroolefin compounds

The subject of the invention is a process for the preparation of fluoroolefin compounds. It relates more particularly to a process for manufacturing a (hydro)fluoroolefin compound comprising (i) bringing at least one compound comprising from three to six carbon atoms, at least two fluorine atoms and at least one hydrogen atom, provided that at least one hydrogen atom and one fluorine atom are located on adjacent carbon atoms, into contact with potassium hydroxide in a stirred reactor, containing an aqueous reaction medium, equipped with at least one inlet for the reactants and with at least one outlet, in order to give the (hydro)fluoroolefin compound, which is separated from the reaction medium in gaseous form, and potassium fluoride, (ii) bringing the potassium fluoride formed in (i) into contact, in an aqueous medium, with calcium hydroxide in order to give potassium hydroxide and to precipitate calcium fluoride, (iii) separation of the calcium fluoride precipitated in step (ii) from the reaction medium and (iv) optionally, the reaction medium is recycled after optional adjustment of the potassium hydroxide concentration to step (i).




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Preparation of fluorinated olefins via catalytic dehydrohalogenation of halogenated hydrocarbons

A process for making a fluorinated olefin having the step of dehydrochlorinating a hydrochlorofluorocarbon having at least one hydrogen atom and at least one chlorine atom on adjacent carbon atoms, preferably carried out in the presence of a catalyst selected from the group consisting of (i) one or more metal halides, (ii) one or more halogenated metal oxides, (iii) one or more zero-valent metals/metal alloys, (iv) a combination of two or more of the foregoing.




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Fluid cocamide monoethanolamide concentrates and methods of preparation

The invention is drawn to fluid concentrate formulations of fatty acid monoethanolamides comprising (a) about 71-76% by weight of one or more C8-C22 fatty acid monoethanolamides, (b) about 15-17% by weight of water, and (c) about 10-12% by weight of one or more hydrotropes, based on the fluid formulation, wherein the fluid formulation is homogeneous, pumpable and color stable at a temperature of less than 55° C. A preferred embodiment is drawn to fluid concentrate formulations of cocamide monoethanolamide (CMEA) consisting of (a) about 71-76% by weight of CMEA, (b) about 15-17% by weight of water, and (c) about 10-12% by weight of glycerol, based on the fluid formulation. Methods of preparing the fluid concentrate formulations mulations are also disclosed. The fluid concentrate formulations of fatty acid monoethanolamides are useful in the preparation of cosmetic and pharmaceutical compositions.




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Heterobifunctional poly(ethylene glycol) derivatives and methods for their preparation

This invention provides a method related to the preparation of derivatives of poly(ethylene glycol), wherein the method comprises increasing the pH of an aqueous composition comprising a poly(ethylene glycol) bearing a —O—(CH2)n—CO2R3 functional group to result in an aqueous composition comprising a poly(ethylene glycol) bearing a —O—(CH2)n—CO2H functional group, wherein R3 is alkyl and (n) in each instance is 1-6.




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Protected aldehydes for use as intermediates in chemical syntheses, and processes for their preparation

A para-methoxy protected benzaldehyde useful in preparation of treprostinil, and of formula: (Formula (1)) is prepared by subjecting to Claisen re-arrangement a substituted benzaldehyde of formula (1a): (Formula (Ia)) to form the m-hydroxy-substituted benzaldehyde of formula (1b): (Formula (Ib)) and then reacting compound (1b) with a p-methoxybenzyl (PMB) compound to form a PMB-substituted benzaldehyde of formula (1).




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Process for the preparation of fluoroalkyl (fluoro)alkyl carbonates and carbamates

Fluoroalkyl alkyl carbonates and fluorosubstituted carbamates which are suitable as additives or solvents in lithium ion batteries are prepared from fluoroalkyl fluoroformates and the respective alcohol or amine. Methanol is the preferred alcohol, dimethylamine and diethylamine are preferred amines. Fluoromethyl methyl carbonate is the preferred compound to be produced. Fluoroalkyl fluoroformates can be prepared from aldehydes and carbonyl fluoride.




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Process for the preparation of 2-cyanophenylboronic acid and esters thereof

The present invention relates to a process for the synthesis of 2-cyanophenylboronic acid and the esters and salts thereof of formula (II), which are intermediates of the synthesis of active pharmaceutical ingredients such as Perampanel or E2040. formula (II): (II).




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Preparation method of aromatic boronate compounds

Preparation method of aromatic boronate compound is provided, in which the is as follows: reacting aromatic amine Ar-NH2, with diboronic ester and alkyl nitrite in the presence of organic solvent, where Ar represents non-heterocyclic aryl. It enables for the first time the preparation of aromatic boronate from aromatic amine in one step by the present method.




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Alanyl glutamine compound and preparation method thereof

A process for preparing a pure alanylglutamine comprises the steps of: 1) reacting N-(α-chloro)-propionyl-glutamine and hydrazine compound to obtain an alanylglutamine crude product; 2) mixing anhydrous methanol and the alanylglutamine crude product to provide a filter cake; 3) dissolving the filter cake in water, heating, adding ethanol, and cooling to yield the pure alanylglutamine.




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Cytosine analogue, a method of preparation of a cytosine analogue, a DNA methyltransferase 1 inhibitor, a method for DNA methylation inhibition, the use of the analogue in the treatment of diseases associated with deviations from normal DNA methylation

A cytosine analog, a method of preparation of a cytosine analog, a DNA methyltransferase 1 inhibitor, and a method for DNA methylation inhibition, is provided for the treatment of diseases associated with deviations from normal DNA methylation. The analog of cytosine may be comprised of 1, N4, 5 and 6-substituted derivatives of cytosine or 5,6-dihydrocytosine, wherein the analog can be described by the chemical formula where R1 is H, R3, R4, 2'-deoxyribosyl, R4 is alkyl or aryl, X is N or C, wherein if X in the analog of formula I is N, then R5 is no substituent and if X in the analog of formula I and/or II is C or if X in the analog of formula II is N, then R5 and R6 are independently alkyl, aryl, hydroxyalkyl, aminoalkyl, hydroxyl, carboxyl, amino group, alkoxyl, aryloxyl, aminoalkyl, aminoaryl, thio group, sulfonyl, sulfinyl or halogen.




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Cellulose ethers having reactive anchor group, modified cellulose ethers obtainable therefrom and methods for the preparation thereof

Non-ionic water-soluble cellulose ethers modified with 3-azido-2-hydroxypropyl groups bound via an ether link are provided having a molar degree of substitution MSAHP in the range from 0.001 to 0.50. Exemplary cellulose ethers are alkyl celluloses, including methyl, hydroxyalkyl (e.g. hydroxyethyl or hydroxypropyl) or alkylhydroxyalkyl cellulose (e.g. methylhydroxyethyl). Reaction products with alkyne compounds are also provided, resulting in a terminal alkyne group. The reaction of azide with the alkyne proceeds as a 1,3-dipolar cycloaddition reaction, advantageously with Cu(I) or ruthenium catalysts. A multiplicity of cellulose ethers can be obtained from the conversion reaction. Variations in the macroscopic properties can be achieved by controlled modification, ranging from increased or reduced viscosity. The reaction, taking place within a few seconds, requires only minimal catalyst. Gel formation is reversible by adjustment of the pH such that a monophasic system (high-viscous fluid) arises again from a biphasic system (gel+low-viscous water phase).




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Processes for the preparation of fesoterodine

The invention relates to improved process for the preparation of fesoterodine and its pharmaceutically acceptable salt, specifically fesoterodine fumarate of formula (1). The invention relates to solid state forms of a novel salt of fesoterodine and process for the preparation thereof. The invention also relates to highly pure fesoterodine fumarate substantially free of impurity X at RRT 1.37. The invention also provides solid particles of pure fesoterodine fumarate wherein 90 volume-percent of the particles (D90) have a size of higher than 200 microns.




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5-aminolevulinic acid derivatives, methods for their preparation and uses thereof

The present invention provides drug conjugates comprising 5-aminolevulinic acid (ALA), an aldehyde and a carboxylic acid that may function as a histone deacetylase inhibitor (HDACI). These conjugates may serve as co-drugs which release a plurality of active species in vivo. The novel drug conjugates may be used, for the treatment or prevention of cancer in PDT-dependent and/or PDT-independent (nonPDT) treatments, as well as for cosmetic uses. In addition the present invention provides novel uses for both the novel and known compounds. According to some embodiments, the present invention provides drug conjugates (co-drugs) comprising (i) ALA, (ii) an aldehyde and (iii) a carboxylic acid that may function as a histone deacetylase inhibitor (HDACO for the treatment of anemia and/or for the induction of erythropoiesis.




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Process for the preparation of the monomer pentabromobenzyl acrylate and polymerization thereof

The invention relates to a process for preparing pentabromobenzyl acrylate through the reaction of pentahalobenzyl halide with a salt of acrylic acid in water-immiscible solvent, wherein said salt is in aqueous form and the reaction is carried out in the presence of a phase transfer catalyst. A process for polymerizing the pentabromobenzyl acrylate in halogenated aromatic solvent and the poly (pentabromobenzyl acrylate) obtained are also disclosed.




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Process for the preparation of isocyanates in the gas phase

Aromatic isocyanates are produced by reacting one or more aromatic primary amines with phosgene in the gas phase. The phosgene and primary aromatic amine(s) are reacted at a temperature above the boiling temperature of the amine(s) in a reactor having a reaction space which is essentially rotationally symmetric to the direction of flow. The flow fate, averaged over the cross-section, of the reaction mixture along the axis of the essentially rotationally symmetric reaction space in the section of the reaction space in which the conversion of the amine groups into isocyanate groups is between 4 and 80% is not more than 8 m/sec. The flow rate averaged over the cross-section of the reaction mixture along the axis of the essentially rotationally symmetric reaction space in the section of the reaction space in which the conversion of the amine groups into isocyanate groups is 4 to 80% is always below the flow rate averaged over the cross-section at the start of this section.




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Gem-dinitro ester compound as energetic material and preparation method thereof

Provided is a gem-dinitro ester compound, represented by Formula 1 below: wherein R is a substituted or unsubstituted straight-chain or side-chain alkyl group of C2˜C12.




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Modified layered double hydroxide (LDH) and a process for preparation thereof for C—C bond forming reactions

The present invention relates to a covalently organo-modified LDH (LDH/APTES) was found to be an efficient and reusable heterogeneous catalyst for C—C bond forming reactions (i.e. Aldol condensation, Knoevenagel condensation, Henry reaction, Michael addition). More particularly, this catalyst shows consistent activity for several cycles in C—C bond forming reaction. These catalysts were successfully characterized by XRD, FT-IR, 29Si CP MAS NMR.




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Intermediate compounds of tamiflu, methods of preparation and uses thereof

Chiral amino compounds, methods of preparation and uses thereof. Tamiflu can be obtained from the said compounds. Multi-substituted chiral tetrahydropyrrolyl amine which can be used as intermediate compounds of medicament can also be produced by the said compounds.




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Process for the preparation of metallocene complexes

A process to prepared bridged bis(indenyl)ligands, comprising the step of reacting a 2-indenylpinacolyl borane compound with a bromosubstituted compound in the presence of a Pd catalyst and a base to form the corresponding bridged bis(indenyl) ligand. The process may further comprise the step of reacting a 2-bromo indene compound with pinacolborane in the presence of a Pd catalyst and a base to form the corresponding 2-indenylpinacolylborane compound. These bridged bis(indenyl)ligands may suitably be used in the preparation of metallocene complexes, such as 2,2'-bis(2-indenyl)biphenyl ZrCl2 and 1,2-bis(2-indenyl)benzene ZrCl2. These metallocene complexes may be used for the polymerization, optionally in the presence of a cocatalyst, of one or more α-olefins, preferably for the polymerization of ethylene.




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Organometallic compound preparation

A method of continuously manufacturing organometallic compounds is provided where two or more reactants are conveyed to a reactor having a laminar flow contacting zone, a heat transfer zone, and a mixing zone having a turbulence-promoting device; and causing the reactants to form the organometallic compound.




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Efficient processes for large scale preparation of phosphaplatins antitumor agents

An efficient process for synthesizing phosphaplatins in large quantities is disclosed by adding platinum complex to a concentrated pyrophosphate solution at pH from between about 6.0 to 8.5. After stirring, the temperature and pH are lowered to precipitate out desired phosphaplatins. Particularly, the disclosed processes reduce the need to use large volumes of starting materials, and shorten the reaction time. In addition, disclosed is a process for recycling un-reacted materials from a first phosphaplatins synthesis.




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Method for bottom-up graphene sheet preparation and bandgap engineering

A combination of a substrate selected from silicon, silicon carbide or a metal and a grapheme precursor having the following properties: (a) an aromatic structure that forms the basis of the graphene structure, said aromatic structure being selected from the group consisting of: benzene, naphthalene, pyrene, anthracene, chrysene, coronene, and phenanthrene, or a cyclic or acyclic structures which can be converted to aromatic structures and (b) functional groups that can react with each other to form additional aromatic structures.




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Substituted phenoxyethyl (isopropyl) acyloxyalkyl phosphonate comprising phosphorusheterocyclic ring and having herbicidal activity, and preparation therefor

A substituted phenoxyethyl(isopropyl)acyloxyalkyl phosphonate having phosphorusheterocyclic ring and having herbicidal activity, with a general formula of I, wherein R represents 5,5-dimethyl-1,3,2-dioxaphosphorinan-2-one-2-yl, or 1-oxo-1-phospha-2,6,7-trioxabicyclo[2,2,2]octan-4-yl, or 1-sulfo-1-phospha-2,6,7-trioxabicyclo 2,6,7-trioxabicyclo[2,2,2]octan-4-yl; R1 represents H, C1-C4 alkyl, phenyl, furyl, pyridyl, or phenyl substituted with methyl, methoxyl, nitro or chloro; R2 represents H, methyl, and methyl only if R in the general formula I is 1-sulfo-1-phospha-2,6,7-trioxabicyclo[2,2,2]octan-4-yl as phosphorusheterocyclic ring; X and Y represent H, halogen, C1-C4 alkyl or trifluoromethyl, and X and Y are the same or different. The compounds according to the present invention may be used as active component of dicotyledonous broadleaf weed herbicides.




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Process for preparation of acetals

A process for the preparation of 1,3:2,4-bis(4-methylbenzylidene)sorbitol (MDBS) and 1,3:2,4-bis(3,4-dimethylbenzylidene)sorbitol (DMDBS) via a dehydrocondensation reaction is disclosed. The reaction is carried out between an aldehyde and an alditol in a mole ratio of 2:1 wherein ionic fluid is used as the acidic catalyst and/or reaction medium. The ionic fluid used in accordance with the present invention is quaternary ammonium salt based ionic liquid.




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Method for preparation of anhydrosugar alcohols

A method is provided for the preparation of anhydrosugar alcohols. The method involves dehydration of a hexitol with a mixed acid of a first acid and second acid, in which the first acid is sulfuric acid and the second acid is at least one sulfur-containing acid or sulfur-containing acid salt selected from the group consisting of p-toluenesulfonic acid, methanesulfonic acid, ethanesulfonic acid, benzenesulfonic acid, naphthalenesulfonic acid and aluminum sulfate. Also provided are methods for purification of the resulting product.




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Process for the preparation of 1-aryl-pyrazol-3-one intermediates useful in the synthesis of sigma receptors inhibitors

The invention relates to a process for preparing 1-aryl-pyrazol-3-one intermediates, tautomers, and salts thereof, to novel intermediates, and to the use of the intermediates in the preparation of sigma receptor inhibitors.