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Topic: Phosphonium salt

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	Phosphonium - Wikipedia, the free encyclopedia
		In chemistry, the phosphonium cation is a positively charged polyatomic ion with the chemical formula PH, resulting from protonation of phosphine.
		Salts containing four alkyl or aryl groups attached to a positive phosphorus are referred to as phosphonium salts.
		Alkyltriphenylphosphonium salts are widely used for the preparation of Wittig reagents for the Wittig reaction.
	en.wikipedia.org /wiki/Phosphonium (86 words)

	Wittig reaction - Wikipedia, the free encyclopedia
		The Wittig reagent is usually prepared from a phosphonium salt, which is in turn made by the reaction of triphenylphosphine with an alkyl halide.
		To form the Wittig reagent (ylide), the phosphonium salt is suspended in a solvent such as diethyl ether or THF and a strong base such as phenyllithium or n-butyllithium is added.
		They can be prepared from the phosphonium salts using weaker bases than butyllithium such as alkoxides and (in some cases) sodium hydroxide.
	en.wikipedia.org /wiki/Wittig_reaction (1433 words)

	Dry electrostatographic developer containing toner particles comprising a vinyl addition polymer containing a ...
		The phosphonium polymers serve as dual function binder/charge-control agents in the toner particles of the inventive electrostatographic developers and have a number of advantages over the non-bonded combinations of vinyl addition polymeric binders and quaternary phosphonium salt charge-control agents described in the prior art.
		Since the quaternary phosphonium salt charge-control moiety is covalently bonded to the polymer, there is no problem of dispersibility, and no such problems have been found to arise when the polymer is mixed with another compatible polymeric binder, in preparing toner particles for some of the developers of the invention.
		In the preferred method, involving grafting phosphonium salts onto vinyl addition polymers the appropriate phosphine is grafted onto the polymer by first halogenating the polymer and then replacing the halogen by reaction with the appropriate lithium phosphide.
	www.freepatentsonline.com /4837392.html (7327 words)

	Novel pigment grinding vehicles - United States Patent 4,035,275
		Generally, the quaternary onium salt may be the salt of boric acid and/or an acid having a dissociation constant greater than boric acid, including organic and inorganic acids.
		Examples of amine salts which may be employed include salts of ammonia; primary, secondary and tertiary amines, and preferably tertiary amines; salts or boric acid or an acid having a dissociation constant greater than that of boric acid and preferably an organic acid having a dissociation constant greater than about 1.times.
		Since the amine salt reacts with the epoxide groups of the epoxy resin employed, in order to provide an epoxy group-containing resin, the stoichiometric amount of amine employed should be less than the stoichiometric equivalent of the epoxide groups present, so that the final resin is provided with one epoxy group per average molecule.
	xrint.com /patents/us/4035275 (8290 words)

	Stabilized aqueous amide antimicrobial composition - United States Patent 4,163,796
		The composition of claim 1 wherein the neutralizing anion, A.sup..crclbar., of the quaternary ammonium or phosphonium salt is chloride or bromide.
		The stabilizers employed in the practice of this invention are quaternary ammonium or phosphonium compounds (i.e., compounds which comprise a quaternized nitrogen or phosphorus atom having four covalent bonds with two, three of four distinct organic radicals and an ionically bonded neutralizing anion).
		The quaternary ammonium or phosphonium stabilizers preferably employed in the practice of this invention comprise a quaternized nitrogen or phosphorus atom having four monovalent saturated hydrocarbon radicals covalently bonded thereto (saturated hydrocarbon radical being as hereinbefore defined) and having a neutralizing anion associated therewith (e.g., ionically bonded thereto).
	xrint.com /patents/us/4163796 (4800 words)

	Phosphonium salt composition - Patent 6482483
		A composition comprising tris(hydroxymethyl)phosphine or phosphorus-containing salts or condensates of those salts with nitrogen-containing compounds coated or absorbed onto a solid or porous substrate is disclosed.
		The salts or condensates are based on tetrakis(hydroxymethyl)phosphonium salts.
		The present invention relates to a solid composition comprising trishydroxymethl phosphine or a tetrakis (hydroxymethyl) phosphonium salt, collectively referred to herein as "THP".
	www.freepatentsonline.com /6482483.html (1547 words)

	CYTEC >> Phosphine Chemicals (Site not responding. Last check: 2007-10-19)
		These compounds, in turn, can be used as precursors for the preparation of a large number of quaternary phosphonium salts by treatment with alkyl or aromatic halides.
		This versatility means that a phosphonium salt can be virtually tailor-made to suit the needs of an end user.
		Phosphonium salts are gaining favour in the field of phase transfer catalysis where their enhanced performance and greater thermal stability make them more attractive than their analogous quaternary ammonium salts.
	www.cytec.com /business/SpecialtyChemicals/ser03.shtm (118 words)

	Some Aspects of the Mitsunobu Reaction
		Given the choice between a primary and secondary alcohol, only the phosphorane and oxyphosphonium salt corresponding to the primary alcohol are observed.
		Formation of the phosphonium salt is facilitated in more polar solvents or with acids of low pKa.
		The mechanism is discused in terms of expulsion of triphenyiphosphine from either an S,S-dithiophosphorane or thiophosphonium thiolate salt.
	www4.gu.edu.au:8080 /adt-root/public/adt-QGU20050902.114151 (418 words)

	Tetrakis(hydroxymethyl) Phosphonium Salts (IARC Summary & Evaluation, Volume 48, 1990)
		Tetrakis(hydroxymethyl) phosphonium sulfate was tested for carcinogenicity by oral administration in one strain of mice and in one strain of rats.
		Tetrakis(hydroxymethyl) phosphonium chloride was tested for carcinogenicity by oral administration in one strain of mice and in one strain of rats.
		Tetrakis(hydroxymethyl) phosphonium chloride induced sister chromatid exchange and chromosomal aberrations in Chinese hamster cells in vitro and, in a single study, mutation in mouse cells in vitro.
	www.inchem.org /documents/iarc/vol48/48-05.html (360 words)

	Pyrazole derivatives patent invention (Site not responding. Last check: 2007-10-19)
		or pharmaceutically acceptable salts, solvates or derivative thereof, wherein R1 to R4, n W, X and Y are defined in the description, and to processes for the preparation thereof, intermediates used in their preparation of, compositions containing them and the uses of such derivatives.
		[0023] Suitable base salts are formed from bases which form non-toxic salts and examples are the sodium, potassium, aluminium, calcium, magnesium, zinc, choline, diolamine, olamine, arginine, glycine, tromethamine, benzathine, lysine, meglumine and diethylamine salts.
		[0029] The compound of formula (I) and pharmaceutically acceptable salts, solvates or derivatives thereof may have the ability to crystallize in more than one form, a characteristic known as polymorphism, and all such polymorphic forms ("polymorphs") are encompassed within the scope of the invention.
	www.freshpatents.com /Pyrazole-derivatives-dt20050106ptan20050004129.php (14582 words)

	Student Abstracts: Ames - Chemistry
		To synthesize the phosphonium salts needed for the production of the alkamides, a variety of organic synthesis techniques were used.
		Synthesizing the first phosphonium salt required initial reflux of chloroacetyl chloride with isobutylamine in ethyl ether.
		The preparation of the second phosphonium salt began with crotonic acid and a bromination reaction.
	www.scied.science.doe.gov /scied/Abstracts2005/Ameschem.htm (795 words)

	U.S. Patent: 5202401 - Acrylic elastomer and its vulcanizable composition - April 13, 1993
		However, the acrylic elastomers having epoxy groups as cross-linking sites have such an advantage as a lower metallic corrosion and thus improvements of the vulcanization rate and the compression set have been investigated for the effective utilization of acrylic elastomers having epoxy groups as cross-linking sites.
		The thus obtained, epoxy group-containing acrylic elastomer can be vulcanized with (1) a cyanuric acid and (2) at least one of a quaternary ammonium salt and phosphonium salt as cross-linking agents.
		Then, the polymerization reaction mixture was salted out, thoroughly washed with water and dried, whereby a copolymer elastomers was obtained.
	www.everypatent.com /comp/pat5202401.html (1596 words)

	MSciprac2
		The mixture was allowed to cool and the precipitated phosphonium salt filtered off and washed with toluene.
		The phosphonium salt was used in the next step without purification.
		A solution of NaOH (14 ml of 30 % w/w) was added to the phosphonium salt and the mixture was refluxed for 45 min.
	www.bris.ac.uk /Depts/Chemistry/RJCox/practical/HW.html (531 words)

	Benzyl trimethyl ammonium chloride¡¢56-93-9 (Site not responding. Last check: 2007-10-19)
		At present,, we mainly produce 40 kinds and 4 series of products, including quaternary ammonium salt series, quaternary ammonium hydrate, quaternary phosphonium hydroxide series, crown ether series and other series.
		Tetramethyl ammonium chloride, Tetraethyl ammonium bromide, Tetrabutyl ammonium bromide, Tetrabutyl ammonium hydrogen sulfate, Tetraphenyl phosphonium bromide, Ethyl triphenyl phosphonium bromide, 4-Dimethylamino pyridine, 18-Crown-6(1,4,7,10,13,16-Hexaoxacyclooctadecane).
		Our institute is located in Xianju county, is next to Linhai city (the national pharmaceutical raw material base of China), is 300km and 100km away from Hangzhou and Haimen port.
	www.chemptc.cn /aboutus_e.htm (229 words)

	Nerapharm (Site not responding. Last check: 2007-10-19)
		Active substance for preparation of drug products applied in veterinary medicine to induce and synchronize rut and cure some reproduction dysfunctions in cattle and hogs, to induce parturition in sows and cure some dysfunctions of sexual apparatus of cattle and hogs.
		PHOSPHONIUM SALT is a white to off white, hygroscopic crystalline material of melting point 203-207°C. It is soluble chlorinated organic solvents, ethanol, methanol, partially soluble in water, insoluble in toluene and hexane.
		PHOSPHONIUM SALT is a key intermediate for manufacture of some types of prostaglandins, which are subsequently used as active ingredients of both human and veterinary drugs
	www.nerapharm.cz /1.php (1319 words)

	Quiz (Site not responding. Last check: 2007-10-19)
		Phosphites are used in the Wittig-Horner modification of the reaction, and a base such as sodium methoxide is sufficient, and this base is easier to handle in the lab.
		Answer: e-Explanation: Triethyl phosphite and benzyl chloride are refluxed together to form a phosphonium salt.
		This phosphonium salt is then reacted with a strong base to produce the reactive ylide.
	orgchem.colorado.edu /labquizzes/wittig/wittigans.html (556 words)

	publications
		A Mild Esterification Process in Phosphonium Salt Ionic Liquid.
		Phosphonium Salts as Room-Temperature Ionic Liquids in Organic Synthesis,
		Heck Reactions of Aryl Halides in Phosphonium Salt Ionic Liquids: Library Screening and Applications.
	www.chemistry.mcmaster.ca /mcnulty/publications.htm (808 words)

	Quaternary Phosphonium Salt Suppliers from The Industrial Resource Network - Distributors, manufacturers, and ...
		Quaternary Phosphonium Salt Suppliers from The Industrial Resource Network - Distributors, manufacturers, and wholesalers of quaternary phosphonium salt
		PowerSourcing is your best source for locating quaternary phosphonium salt suppliers.
		Quickly find quaternary phosphonium salt and thousands of other products and services for purchasing and research.
	www.powersourcing.com /sg/quaternaryphosphoniumsalt.htm (145 words)

	JCE 2002 (79) 498 [Apr] Keto-Enol Tautomers in a Carbonyl Phosphonium Salt
		JCE 2002 (79) 498 [Apr] Keto-Enol Tautomers in a Carbonyl Phosphonium Salt
		Supplementary NMR data is provided for an experiment previously published in this Journal describing the synthesis of carbonyl-stabilized ylides.
		The new data suggest that the keto-enol tautomerism is taking place in the phosphonium ion.
	jchemed.chem.wisc.edu /Journal/issues/2002/Apr/abs498.html (170 words)

	Publications
		Reactivity of Phosphorous-Centered Radicals Generated during the Photoreaction of Diphenylphosphinous Acid with 10-Methylacridinium Salt
		Reaction of Diphenylphosphine Oxide with a 10-methylacridinium Salt.
		Kinetic Study on the Formation and Decomposition of Phosphonium Intermediates
	boc.kuicr.kyoto-u.ac.jp /Lab/publications.html (5767 words)

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