摘要:
A one pot synthetic method for making a bridged cyclopentadienyl/fluorenyl type ligand and the corresponding ansa metallocene polymerization catalyst. In a key step, a cyclopentadienide/fluorenide dianion is prepared by combining a fluorene compound, a fulvene compound, and at least 2 molar equivalents of KN(SiMe 3 ) 2 in any order in the presence of an ether solvent under ambient conditions. Reaction of the cyclopentadienide/fluorenide dianion with a Group IV transition metal chloride, followed by alkylation gives a metallocene polymerization catalyst in good yields.
摘要:
The present invention relates to a novel compound, its use as an initiator in anionic polymerizations yielding norbornene-terminated homopolymers of block copolymers, and the further use of said norbornene-terminated polymers as macromonomers in the preparation of graft copolymers.
摘要:
The present specification relates to a sulfonate-based compound, a polymer electrolyte membrane using the same, a membrane electrode assembly containing the same, and a fuel cell containing the same.
摘要:
The present invention relates to a process for preparing a material having the formula: ( M x H y ) +4 ( P 2 O 7 ) -4 : where M is a cation selected from the group consisting of monovalent cations, divalent cations, and trivalent cations; H is hydrogen, P 2 O 7 is the pyrophosphate anion, and y is a number between 2.2 and 3.8; and x is a value sufficient to balance the overall charge of said compound comprising mixing and heating 105 - 1 12% polyphosphoric acid or pyrophosphoric and a compound having a monovalent metal cation or a compound having a divalent metal cation or a compound having a trivalent metal cation.
摘要翻译:本发明涉及一种制备具有下式的材料的方法:(MxHy)+4(P2O7)-4:其中M是选自一价阳离子,二价阳离子和三价阳离子的阳离子; H是氢,P 2 O 7是焦磷酸根阴离子,y是2.2和3.8之间的数; 并且x是足以平衡所述化合物的总电荷的值,包括混合和加热105-112%的多磷酸或焦磷酸和具有一价金属阳离子的化合物或具有二价金属阳离子的化合物或具有三价金属的化合物 阳离子。
摘要:
The invention relates to novel crystalline salts of 5-[(lZ,2E)-2-methyl-3- phenyIpropenylidene]-4-oxo-2-thioxo-3-thiazolidineaeetic acid. The preparation and characterization of the crystalline salts according to various embodiments of the invention is described. The invention also relates to pharmaceutical compositions containing the novel crystalline salts and the therapeutic use of the novel crystalline salts to treat and/or prevent various conditions, including treating and/or preventing diabetic complications, inhibiting aldose reductase, and affording cardioprotection in patients who may be non-diabetic.
摘要:
The invention concerns a novel method for preparing tetrakis(pentafluorophenyl)borate derivatives of general formula MB(C6F5)4, M being selected among Na , Li , or K , wherein: (a) a C6F5X solution, X being selected among H, Cl, Br or I, in anhydrous butylic ether is contacted with an alkyllithium, the mol ratio of C6F5X/alkyllithium being 1 to 1.1, and the alkyl radical, linear or branched comprising 1 to 10 carbon atoms; (b) the resulting product is contacted with previously non-dissolved BR3, R, identical or different being selected among a chlorine atom, a fluorine atom, a bromine atom, an alkoxy radical comprising between 1 and 4 carbon atoms.
摘要翻译:本发明涉及制备通式MB(C6F5)4的四(五氟苯基)硼酸盐衍生物的新方法,M选自Na +,Li +或K +,其中:(a)C 6 F 5 X 溶液中,选自H,Cl,Br或I的无水丁基醚中的X与烷基锂接触,C 6 F 5 X /烷基锂的摩尔比为1〜1.1,直链或支链的碳原子数为1〜10的烷基 ; (b)将所得产物与之前未溶解的BR 3,R 3相同或不同,选自氯原子,氟原子,溴原子,含有1至4个碳原子的烷氧基。
摘要:
(1) Alkali metal diarylphosphides are formed by mixing triarylphosphine with, and preferably introducing triarylphosphine into, a two-phase mixture one or more alkali metals, preferably a mixture or alloy of sodium and potassium, in an anhydrous organic liquid diluent in the presence of molecular hydrogen. (2) To form a cycloalkyldiarylphosphine, at least a portion of the reaction mixture formed as in (1) (or alkali metal diarylphosphide recovered therefrom) and cycloalkyl mesylate or tosylate are mixed together and maintained under suitable reaction conditions. Reaction (2) is driven by the presence of residual sodium from reaction (1). Conduct of reaction (2) under a hydrogen atmosphere suppresses undesirable side reactions.
摘要:
This invention relates to methods for the production of various metal salts of 5-sulfoisophthalic acid including those where the metal cation is selected from the group consisting of silver (I), sodium, potassium, rubidium, cesium, magnesium, calcium, strontium, barium, manganese (II), iron (II), cobalt (II), nickel (II), copper (I), copper (II), zinc, yttrium, and cadmium. The methods utilize a solvent system that comprises acetic acid or water or a mixture of both. The invention also encompasses the various metal salts of 5-sulfoisophthalic acid.