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	Rearrangement
		Rearrangements consisting of consecutive 1,2-shifts often take place in a concerted, and therefore stereospecific fashion; however, it must not be assumed that the group shifts are simultaneous.
		Rearrangement to a 2º-carbocation is favored by relief of small-ring strain in the case of pinene, and relief of steric congestion in the case of camphene.
		The rearrangement of acyl nitrenes to isocyanates that is the crux of the Hofmann, Curtius and Lossen rearrangements, is paralleled by the rearrangement of acyl carbenes to ketenes, a transformation called the Wolff rearrangement.
	www.cem.msu.edu /~reusch/VirtualText/rearrang.htm (7059 words)

	beckmann_rearrangement (Site not responding. Last check: 2007-10-09)
		The Beckmann rearrangement, named after the German chemist Ernst Beckmann, is an acid-catalyzed rearrangement of an oxime to an amide.
		The reaction mechanism of the Beckmann rearrangement is generally believed to consist of an alkyl migration with expulsion of the hydroxyl group to form a nitrilium ion followed by hydrolysis.
		The Beckmann reaction is known to be catalyzed by cyanuric chloride and zinc chloride co-catalyst.
	www.loseweight800.com /wiki/?title=Beckmann_rearrangement (421 words)

	One thing leads to another
		Kolbe played a minor role in Beckmann's supervision, and Beckmann was one of only three of Kolbe's students to rise eventually to the rank of full professor, yet he always entertained a great respect for his mentor and was clearly influenced by his values.
		Beckmann assumed that an intermediate was formed during the reaction of isonitroso compounds [oximes] with acids.
		Beckmann's final publication from this Leipzig period reported the formation of a dark blue solution when sodium was added to benzophenone in dry ether.
	www.rsc.org /chemistryworld/Issues/2003/November/leads.asp (2162 words)

	Beckmann rearrangement - Wikipedia, the free encyclopedia
		The rearrangement of acetone oxime in the Beckmann solution involves three acetic acid molecules and one proton (present as an oxonium ion).
		In the transition state leading to the iminium ion (σ - complex), the methyl group migrates to the nitrogen atom in a concerted reaction and the hydroxyl group is expulsed.
		"The Beckmann reactions: rearrangement, elimination-additions, fragmentations, and rearrangement-cyclizations.
	en.wikipedia.org /wiki/Beckmann_rearrangement (493 words)

	Is the Beckmann rearrangement a concerted or stepwise reaction? A computational study.
		Is the Beckmann rearrangement a concerted or stepwise reaction?
		Beckmann Rearrangement of (15)N-Cyclohexanone Oxime on Zeolites Silicalite-1, H-ZSM-5, and H-[B]ZSM-5 Studied by Solid-State NMR Spectroscopy.
		The rearrangement step, using the bare cluster model, is the rate determining step of the entire reaction of these oxime molecules of which the energy barrier is between 50-70 kcal mol(-1).
	database-management-systems.lib.bioinfo.pl /pmid:16355980 (1513 words)

	Beckmann rearrangement
		The rearrangement of an oxim to the amide in conc.
		This example reaction starting with hexanon to the Caprolactam is the most important application of the Beckmann rearrangement.
		The caprolactam is hydrolysed and the polymerized to Nylon.
	www.ebroadcast.com.au /lookup/encyclopedia/be/Beckmann_rearrangement.html (49 words)

	U.S. Patent: 5041666 - Method for the production of 3,3'4,4'-tetraaminobiphenyl - August 20, 1991
		The method of claim 9 wherein said oximation (step 2) and Beckmann rearrangement (step 3) are combined by reacting said DAcB with a hydroxylamine salt in the presence of anhydrous acetic acid or anhydrous formic acid as solvent and the temperature of reaction is no lower than about 75.degree.
		If it is desired to combine the dioximation and double Beckmann rearranqement in one reaction, the conditions described previously for oximation may be used except that the solvent/catalyst employed is an anhydrous acidic solvent such as formic, acetic, or methanesulfonic acid in the absence of a base.
		These examples illustrate the double Beckmann rearrangement of DiAcB dioxime to form DiAcBz in accordance with equation III, using the procedure of Example 15 except that the solvent was ethyl acetate (EtOAc) or a mixture of EtOAc and tetrahydrofuran (THF) in a 4:1 weight ratio and the quantity of thionyl chloride (SOCl.sub.2) was varied.
	www.everypatent.com /comp/pat5041666.html (3818 words)

	Process for producing N-acyl-hydroxy aromatic amines - Patent 4524217
		The examples of this patent are limited to the rearrangement of esters of higher fatty acids with the yields ranging from 55 to 95%.
		Pearson et al, Journal of the American Chemical Society 75 5905-5908 (Dec. 5, 1953) disclose the formation of hydrazones from ketones by reaction with hydrazine hydrate and the rearrangement of the hydrazone to the amide by reaction with sodium nitrite and concentrated sulfuric acid.
		The ketoxime is converted into the corresponding N-acyl-hydroxy aromatic amine by a Beckmann rearrangement as shown in equations (III) and (IV), by contacting the ketoxime with a catalyst for the reaction at a temperature, for example of 0.degree.
	www.freepatentsonline.com /4524217.html (2864 words)

	publications
		Beckmann, P.-M. Kloetzel, E. Krueger and P.A. Penczek (2004) Rearrangement of the 16S precursor subunits is essential for the formation of the active 20S proteasome.
		Beckmann, D. Bubeck, R. Grassucci, P. Penczek, A. Verschoor, G. Blobel and J. Frank (1997), Alignment of conduits for the nascent polypeptide chain in the ribosome-Sec61 complex.
		Beckmann, C. Lindschau, H. Haller and K. Buchner (1995), Bradykinin induces rise of free calcium in nuclei of neuroblastoma x glioma hybrid NG 108-15 cells.
	www.beckmann-lab.de /publications/publications.html (467 words)

	Method for manufacturing zeolite and method for manufacturing .epsilon.-caprolactam - Patent # 7060645 - PatentGenius
		C. A method for manufacturing.epsilon.-caprolactam wherein the.epsilon.-caprolactam is manufactured by Beckmann rearrangement reaction of cyclohexanone oxime in a gaseous phase in the presence of the zeolite manufactured by the methodaccording to claim 1.
		Conventionally, a method of Beckmann rearrangement reaction of cyclohexanone oxime in a gaseous phase using zeolites as a catalyst has been known as one of methods for manufacturing.epsilon.-caprolactam.
		As reaction conditions for Beckmann rearrangement, a reaction temperature is usually 250 to 500.degree.
	www.patentgenius.com /patent/7060645.html (2984 words)

	Department of Chemistry (Site not responding. Last check: 2007-10-09)
		Carbon migration: Wagner-Meerwein rearrangement, Pinacol rearrangement, Benzilic acid rearrangement, Rearrangement involving diazomethane, Rearrangement of saturated carbon chains.
		Stevens rearrangement, Farvoskii rearrangement and Proof of mechanism of Farvoskii rearrangement.
		Intramolecular migration from oxygen to carbon as exemplified by the Claisen and Fries rearrangements of aryl allyl ethers Intermolecular migration from nitrogen to carbon as illustrated by Hydrazobenzenes - Benzidine rearrangement Intermolecular migration from nitrogen to carbon, N-Arylazoanilines
	www.uz.ac.zw /science/chemistry/courses/ch213.htm (230 words)

	The Yamamoto Group - The University of Chicago
		Beckmann rearrangement of oxime sulfonates by Grignard reagents, K. Hattori, K. Maruoka, H. Yamamoto, Tetrahedron Lett., 23, 3395 (1982).
		Rearrangement of trans-stilbene oxide to diphenylacetaldehyde with catalytic methylaluminum bis(4-bromo-2,6-di-tert-butylphenoxide), T. Ooi, K. Maruoka, H. Yamamoto, Organic Syn.
		Tris(pentafluorophenyl)boron as an efficient catalyst in the stereoselective rearrangement of epoxides, K. Ishihara, N. Hanaki, H. Yamamoto, Synlett, 721 (1995).
	yamamotogroup.uchicago.edu /work.html (9185 words)

	Process for obtaining coarsely crystalline pure ammonium sulfate - Patent 4138472
		A process as set forth in claim 1, in which the vapors obtained during evaporation are used to concentrate ammonium sulfate solutions which have been obtained by reaction of cyclohexanone with hydroxylammonium sulfate in the presence of ammonia.
		1,194,863 discloses a process in which reaction mixtures which have been obtained by Beckmann rearrangement of cyclohexanone-oxime with sulfuric acid or oleum are neutralized with ammonia at from 30.degree.
		The process starts from reaction mixtures which have been obtained by Beckmann rearrangement of cyclohexanone-oxime with sulfuric acid or oleum.
	www.freepatentsonline.com /4138472.html (1595 words)

	Need beckmann rearrangement? Search rearrangement (Site not responding. Last check: 2007-10-09)
		Ig gene rearrangement process • sequence analysis • identical TCR-ß chains paired Abstract the diagnostic usefulness of Gerlach, C Menzel, and G. group I, patients without the mobility of his IV Distance N-O no difference was found 1(10)-double bond (the reaction Beckmann rearrangement anomalies.
		Am J secondary, tertiary and H-free light chain genes occurs Until recently, Beckmann rearrangement 100 ng genomic DNA or rearrangement involving their N-CH3 Site Map TABLE OF by J Med Genet or frozen or fixed.
		Citation Map the diagnostic usefulness of rearrangement into the mature Citation Map an exact karyotype interpretation should be connected to rearrangement.
	rearrangement.intcom.org /beckmann_rearrangement.htm (1791 words)

	IngentaConnect The Catalysis of Vapor-Phase Beckmann Rearrangement for the Produ... (Site not responding. Last check: 2007-10-09)
		In the process, cyclohexanone oxime is rearranged into -caprolactam using a zeolite as a catalyst instead of sulfuric acid.
		We propose that the coordination between the NOH group of cyclohexanone oxime molecule and the nest silanols through hydrogen bonding is responsible for the reaction.
		The reaction mechanism of Beckmann rearrangement under vapor-phase conditions is the same as in the liquid phase, namely, the alkyl group in anti-position against the hydroxyl group of the oxime migrates to the nitrogen atom's position.
	www.ingentaconnect.com /content/klu/cats/2003/00000007/00000004/00476483 (423 words)

	1,2-rearrangement - Wikipedia, the free encyclopedia
		a carbocation by heterolysis in a nucleophilic rearrangement or anionotropic rearrangement
		This observation can be explained on the basis of Hückel's rule.
		Whitmore, Frank C. "The common basis of molecular rearrangements".
	en.wikipedia.org /wiki/1,2-rearrangement (360 words)

	Problem Set #1
		In the Fries rearrangement, aryl esters such as phenyl acetate are converted to acyl phenols such as 2-hydroxyacetophenone by the action of Lewis acids (see below).
		Devise an experiment to show whether this rearrangement is intra- or intermolecular in nature.
		In the Beckmann rearrangement of benzophenone oxime under acidic conditions to give N-phenylbenzamide (see below), how could one determine whether it is the phenyl group oriented syn or anti to the hydroxyl group that migrates or whether it is possible for either phenyl group to migrate?
	clem.mscd.edu /~wiederm/advorgchem/401problemset1.htm (630 words)

	Dr. Chawalit Ngamcharussrivichai
		Tatsumi, T.; Ngamcharussrivichai, C. “Beckmann Rearrangement Catalyzed by Large-pore Zeolite and Mesoporous Molecular Sieve Catalysts” 1st Green and Sustainable Chemistry Symposium, Tokyo, Japan, October 12 – 13, 2000.
		Ngamcharussrivichai, C.; Wu, P.; Tatsumi, T. “Catalytic Activity of Mesoporous Molecular Sieves in Liquid-phase Beckmann Rearrangement” 30th Petroleum and Petrochemical Forum, Tokyo, Japan, November 6 – 7, 2000.
		Ngamcharussrivichai, C.; Wu, P.; Tatsumi, T. “Liquid-phase Beckmann Rearrangement Catalyzed by Large-pore Zeolites and Mesoporous Molecular Sieves” 13th International Zeolite Conference, Montpellier, France, July 8 – 13, 2001.
	www.sc.chula.ac.th /department/Chemical_Technology/staff/cnc.htm (621 words)

	Prof. Yamamoto - Chemistry Department - University of Chicago
		In his early days in Nagoya, Yamamoto discovered the Beckmann rearrangement-alkylation reaction using organoaluminum reagent, which is now widely utilized for the construction of heterocyclic structures.
		He also reported the Beckmann rearrangement-cyclization sequence, which was employed in his straightforward synthesis of muscopyridine.
		These reagents were successfully utilized for the selective alkylation of cyclic ketones and aldehydes to generate equatorial alcohol and an anti-Cram type product, respectively, for discrimination between two different ethers, aldehydes, ketones, or esters by complexations, for trans- and cis-selective Claisen rearrangement, for regioselective Diels-Alder reaction, and for new epoxide-aldehyde rearrangement.
	chemistry.uchicago.edu /fac/yamamoto.shtml (1429 words)

	Process Economics Report 7: Caprolactam
		During caprolactam manufacture, ammonium sulfate is produced in the hydroxylamine formation and in the Beckmann rearrangement steps.
		Extracting the caprolactam from the rearrangement mixture eliminates the need for neutralization and thus avoids the formation of ammonium sulfate.
		DSM also offers a process in which the Beckmann rearrangement mixture is only partially neutralized to ammonium bisulfate.
	www.sriconsulting.com /PEP/Public/Reports/Phase_X/RP007B (295 words)

	Nitrile synthesis by oxidation, rearrangement, dehydration
		Different ketoximes, which are prepared from the corresponding ketones, undergo the Beckmann rearrangement at room temperature in excellent yields upon treatment with 2,4,6-trichloro[1,3,5]triazine in N,N-dimethylformamide.
		Nitriles are obtained from aldoximes using the same procedure.
		A variety of ketoximes undergo the Beckmann rearrangement when heated with 0.5 molar equiv.
	www.organic-chemistry.org /synthesis/C3N/nitriles.shtm (242 words)

	Caprolactam Purification : Removal of inorganic and amine impurities (Site not responding. Last check: 2007-10-09)
		Most commercial production of caprolactam is via the cyclohexanone oximation and Beckmann rearrangement route.
		Because this process involves use of oleum for the Beckmann rearrangement, followed by neutralization with ammonia or ammonium hydroxide, the process generates large quantities of ammonium sulfate as a waste.
		The caprolactam is purified by vacuum crystallization or vacuum distillation but small quantities (ppm) of ammonium sulfate remain and contaminate the aqueous caprolactam solution product.
	www.rohmhaas.com /ionexchange/IP/caprolactam.htm (217 words)

	PEP Review: 98-15: Caprolactam Via Gas Phase Beckmann Rearrangement
		This review examines the technology represented by recent patents in gas phase Beckmann rearrangement of cyclohexanone oxime to caprolactam.
		The issue is relevant because of a recent process development joint venture between Sumitomo (for the oxime rearrangement step) and Enichem (for oxime production).
		The conclusion of this review finds that both steps, as illustrated by the corresponding patents, do not appear to be competitive with current best practices.
	www.sriconsulting.com /PEP/Reports/Phase_98/RW98-15/RW98-15.html (341 words)

	Chem Systems PERP Program Newsletter (Site not responding. Last check: 2007-10-09)
		Enhancements to Conventional Technology - the current commercial routes to caprolactam production are based on aromatic feedstocks: namely benzene, phenol and toluene.
		The typical caprolactam process involves production of cyclohexanone, oximation with hydroxylamine and finally the so-called “Beckmann Rearrangement”.
		Recently Sumitomo has announced plans to build a new caprolactam plant in Japan using its fluid bed gas-phase zeolite-catalyzed Beckmann rearrangement combined with EniChem’s hydrogen peroxide-catalyzed “ammoximation” reaction.
	www.chemsystems.com /newsletters/perp/april01_99_4.cfm (542 words)

	Cyanuric Chloride as a Mild and Active Beckmann Rearrangement Catalyst (Site not responding. Last check: 2007-10-09)
		Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8603, Japan, and Department of Chemistry, The University of Chicago, 5735 South Ellis Avenue, Chicago, Illinois 60637
		The first general organocatalytic Beckmann rearrangement of ketoximes into amides has been realized by the catalytic use of cyanuric chloride.
		For example, azacyclotridecan-2-one, which is synthetically useful as a starting material for nylon-12, was prepared in quantitative yield by the Beckmann rearrangement of cyclododecanone oxime (100 mmol scale) catalyzed by cyanuric chloride (0.5 mol %) and ZnCl
	pubs.acs.org /cgi-bin/abstract.cgi/jacsat/2005/127/i32/abs/ja053441x.html (123 words)

	July in Chemistry
		Sergei Semenovich Nametkin born 1876: terpene chemistry; rearrangement of camphenes.
		Ernst Otto Beckmann born 1853: Beckmann rearrangement in organic chemistry
		Unmanned mission included physical and chemical characterization of Martian surface.
	web.lemoyne.edu /~giunta/July.html (1427 words)

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