ketene dimers from acid halides journal of the american

ketene dimers from acid halides journal of the american

ketene dimers from acid halides journal of the american

Ketene Dimers from Acid Halides | Journal of the American ...May 01, 2002 · Journal of the American Chemical Society 1953, 75 (18) , 4590-4591. DOI: 10.1021/ja01114a512. John R. Johnson, V. J. Shiner Jr.. The Structure of Ketene Dimer. Journal of the American Chemical Society 1953, 75 (6) , 1350-1355. DOI: 10.1021/ja01102a026.

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US5725731A - 2-oxetanone sizing agents comprising ketene dimers from acid halides journal of the american

US5725731A US08/439,057 US43905795A US5725731A US 5725731 A US5725731 A US 5725731A US 43905795 A US43905795 A US 43905795A US 5725731 A US5725731 A US 5725731A Authority US United States Prior art keywords fatty acid composition mole acid straight chain Prior art date 1995-05-08 Legal status (The legal status is an assumption and is not a legal conclusion.US5484952A - Process for the manufacture of alkyl ketene ketene dimers from acid halides journal of the americanUS5484952A US08/238,293 US23829394A US5484952A US 5484952 A US5484952 A US 5484952A US 23829394 A US23829394 A US 23829394A US 5484952 A US5484952 A US 5484952A Authority US United States Prior art keywords solvent alkyl ketene ketene dimer making tertiary amine Prior art date 1993-05-10 Legal status (The legal status is an assumption and is not a legal conclusion.US4614546A - Sizes based on ketene dimers - Google PatentsNew aqueous sizes, in particular paper sizes, are made available which contain (a) ketene dimers of the formula ##STR1## in which R 1 and R 2 can be identical or different and represent hydrocarbon radicals having 6 to 30 carbon atoms, (b) amine-modified starch, (c) hydrophobic compound(s) which contain(s) one or more functional groups which are reactive towards OH groups within a pH range of ketene dimers from acid halides journal of the american

Three-Component Synthesis of Cyclic Enaminones via Ketene ketene dimers from acid halides journal of the american

May 06, 2011 · Ketenes, first discovered by Staudinger in 1905, are among the best studied intermediates in organic chemistry. 1 Their versatile reactivity provides access to a number of valuable structural motifs. Ketenes can be readily prepared from several precursors including diazoketones and acid halides, which further underscores their value in synthetic organic chemistry. 2Theoretical Research on the Mechanism of the Dimerization ketene dimers from acid halides journal of the americanAlkyl ketene dimer (AKD) also called AKD wax and alkenyl Succinic Anhydride (ASA) are wax like chemicals. AKD (alkyl ketene dimers, I) is an excellent neutral sizing agent and is widely used in the paper making industry [13]. Traditionally rosin (acidic sizing) was used as a paper sizing material.The effects of AKD oligomers present in AKD wax on ketene dimers from acid halides journal of the americanThe AKD oligomers prepared in this study had molecular mass values ranging from 800 to 10,000 with a weight average molecular mass of 2,300, which corresponded to 9 ketenes or 4.5 ketene dimers ketene dimers from acid halides journal of the american

The effects of AKD oligomers present in AKD wax on ketene dimers from acid halides journal of the american

The AKD oligomers prepared in this study had molecular mass values ranging from 800 to 10,000 with a weight average molecular mass of 2,300, which corresponded to 9 ketenes or 4.5 ketene dimers ketene dimers from acid halides journal of the americanThe First Century of Ketenes (19052005): The Birth of a ketene dimers from acid halides journal of the americanKetenes have always attracted many of the most talented individuals in chemistry, including many Nobel prize winners. 23 Ketenes have found many industrial applications, ranging from the seemingly mundane manufacture of acetic acid and acetic anhydride, to the widespread use of ketene dimers from fatty acids as coatings for paper, 24a the sophisticated application of the Süs photochemical Wolff rearrangement 24b The Development of the First Catalyzed Reaction of Ketenes ketene dimers from acid halides journal of the americanCatalytic, Asymmetric Preparation of Ketene Dimers from Acid Chlorides. Organic Letters 2003, 5 (24) , 4745-4748. DOI: 10.1021/ol0359517. Alle Bruggink,, Rob Schoevaart, and, Tom Kieboom. Concepts of Nature in Organic Synthesis: Cascade Catalysis and Multistep Conversions in Concert.

Substituted ketene elimination from acid chlorides induced ketene dimers from acid halides journal of the american

Jan 12, 1988 · 255 Journal of Organometallic Chemistry, 338 (1988) 25560 Elsevier Sequoia S.A., Lausanne Printed in The Netherlands Substituted ketene elimination from acid chlorides induced by ruthenium(O) compounds Shanti Singh and Michael C. Baird* Department of Chemistry, Queen University, Kingston, K7L 3N6 (Canada) (Received May 14th, 1987) Abstract The compound Ru(CO)2 Structure and Rearrangement of Neutral Phenylketene DimerArticle in Journal of the American Chemical ketene dimers from acid halides journal of the american substitution between potassium thioacetate and alkyl halides followed by fragmentation. ketene dimers from acid halides journal of the american for the ketene dimers and related structures were ketene dimers from acid halides journal of the americanStructure and Mechanism in Ketene Chemistry - ScienceDirectJan 01, 2014 · The parent ketene -lactone dimer 35 is commercially available, and upon thermolysis provides convenient access to ketene . 29a For the parent the assignment of the structure of the dimer as either the -lactone (35) or the 1,3-cyclobutanedione (36) was controversial for a long period. 29b A pioneering depiction of the alternatives for ketene ketene dimers from acid halides journal of the american

Structure and Mechanism in Ketene Chemistry - ScienceDirect

Jan 01, 2014 · The parent ketene -lactone dimer 35 is commercially available, and upon thermolysis provides convenient access to ketene . 29a For the parent the assignment of the structure of the dimer as either the -lactone (35) or the 1,3-cyclobutanedione (36) was controversial for a long period. 29b A pioneering depiction of the alternatives for ketene ketene dimers from acid halides journal of the americanSilyl Ketene Imines: Highly Versatile Nucleophiles for ketene dimers from acid halides journal of the americanOct 01, 2012 · 1. Introduction. Silyl ketene imines (SKIs) are a class of silylated nucleophiles prepared by the selective N silylation of nitrile anions with electrophilic silylating reagents (1; Scheme 1A).SKIs belong to a broader class of compounds known as cumulenes, which are molecules possessing at least two or more cumulative double bonds, and include functional groups such as allenes and ketenes. []Sciencemadness Discussion Board - Acetic anhydride ketene dimers from acid halides journal of the americanOct 09, 2002 · Now ketene process is absolutely hard and waytoo dangerous to do in a lab. There are many ways to make Ac2O, but all of them involve toxic halides! The general idea is to get CH3-CO-Cl; now use your brains how to get it from acid halides! Most of acid halides are easily done, but I'm a bit tired today, maybe another day!

Research Article Theoretical Research on the Mechanism

of all, a reaction between acid halides and triethylamine to form a monoalkyl ketene intermediate: C O Cl R CH C O RCH 2 + (C 2 H 5)3 N + (C 2 H 5)3 N HCl en, the alkyl ketene dimerization reaction occurs quickly producing AKD products: 2R CH COR CH O CH O R In the dimerization reaction, alkyl ketene always forms four-ring compounds. It is of ketene dimers from acid halides journal of the americanProcess for the manufacture of alkyl ketene dimers by ketene dimers from acid halides journal of the americanJun 11, 1996 · I claim: 1. A process for the synthesis of alkyl ketene dimers by the dehydrohalogenation of a C 8-C 22 saturated or unsaturated linear fatty acid halide, or a mixture of C 8-C 22 linear fatty acid halides, comprising reacting the fatty acid halide with a cyclic tertiary amine in a solvent selected from the group consisting of alkanes and cycloalkanes at a temperature of up to 75° C ketene dimers from acid halides journal of the americanPaper sizing by liquid-type ketene dimers. Part 1 ketene dimers from acid halides journal of the americanThe AKD oligomers prepared in this study had molecular mass values ranging from 800 to 10,000 with a weight average molecular mass of 2,300, which corresponded to 9 ketenes or 4.5 ketene dimers ketene dimers from acid halides journal of the american

Novel ketene formation by reactions of acid chlorides with ketene dimers from acid halides journal of the american

Mar 05, 1991 · This type of ketene formation was found to depend largely on the acid chloride used. Phenylacetyl chloride was also found to react with 1 under CO at r.t. to give 3 (68%) and the IR spectrum of the reaction mixture exhibited absorptions at 1905, 1878, and 1710 cm-' indicating the formation of phenylketene dimer [10].Ketene Dimers from Acid Halides | Journal of the American ketene dimers from acid halides journal of the americanThis article is cited by 91 publications. Shi Chen, Ahmad A. Ibrahim, Nicholas J. Peraino, Divya Nalla, Mukulesh Mondal, Maxwell Van Raaphorst, and Nessan J. Kerrigan .Ketene Dimers from Acid Halides | Journal of the American ketene dimers from acid halides journal of the americanMay 01, 2002 · Journal of the American Chemical Society 1953, 75 (18) , 4590-4591. DOI: 10.1021/ja01114a512. John R. Johnson, V. J. Shiner Jr.. The Structure of Ketene Dimer. Journal of the American Chemical Society 1953, 75 (6) , 1350-1355. DOI: 10.1021/ja01102a026.

Journal of the American Chemical Society | Vol 69, No 10

Ketene Dimers from Acid Halides. J. C. Sauer; Journal of the American Chemical Society 1947, ketene dimers from acid halides journal of the american Journal of the American Chemical Society 1947, ketene dimers from acid halides journal of the americanEPO - T 0458/99 (Ketene dimers/EKA) of 5.11.2002A process for the production of ketene dimers from fatty acid halides by reaction with tertiary amines, characterised in that at least 1.15 moles of tertiary amine that is liquid at the reaction conditions is used per mole of fatty acid halide and the process is carried out in the presence of not more than 10% by weight, based on the amount of ketene dimers from acid halides journal of the americanEPO - T 0355/99 (Ketene dimers / EKA Chemicals) of 30.7.2002Jul 30, 2002 · A process for the production of ketene dimers from fatty acid halides by reaction with tertiary amines, characterised in that the process is operated batchwise and that the reaction is started in the presence of an initial reaction mixture containing ketene dimer and pre-prepared crystals of tertiary amine hydrogen halide and is carried out in ketene dimers from acid halides journal of the american

EP0624579A1 - Process for the manufacture of alkyl ketene ketene dimers from acid halides journal of the american

A process for making an alkyl ketene dimer by the dehydrohalogenation reaction of a C - C aliphatic fatty acid chloride with a tertiary amine in an inert solvent and the product of the process; the solvent comprising at an oxygenated hydrocarbon.Development of a New Lewis Acid-Catalyzed Claisen ketene dimers from acid halides journal of the americanhalogenation of acid halides is a common method for cumulene production,10,11 we selected acid chlorides as an in situ source of ketene for this survey. Our catalytic Claisen strategy was first evaluated using propionyl chloride with (E)-crotyl morpholine12 in the presence of i-Pr2EtN and a series of metal salts. As revealed in Table 1,Catalytic, Enantioselective [4 2]-Cycloadditions of Ketene ketene dimers from acid halides journal of the americanmmol acid halide, and 0.55 mmol 1a at -78 °C with slow addition of the acid halide over 5 h employed for R-aryl acid halides (2c, e, f). Yields given are for isolated products. Chart 2. Various Chiral o-Quinone Adducts Chart 3. Conversion of Cycloadducts to R-Hydroxyesters COMMUNICATIONS J. AM. CHEM. SOC. 9 VOL. 128, NO. 6, 2006 1811

Catalytic, Enantioselective [4 2]-Cycloadditions of Ketene ketene dimers from acid halides journal of the american

mmol acid halide, and 0.55 mmol 1a at -78 °C with slow addition of the acid halide over 5 h employed for R-aryl acid halides (2c, e, f). Yields given are for isolated products. Chart 2. Various Chiral o-Quinone Adducts Chart 3. Conversion of Cycloadducts to R-Hydroxyesters COMMUNICATIONS J. AM. CHEM. SOC. 9 VOL. 128, NO. 6, 2006 1811Catalytic, Asymmetric Preparation of Ketene Dimers from ketene dimers from acid halides journal of the americanCatalytic, Asymmetric Preparation of Ketene Dimers from Acid Chlorides Article in Organic Letters 5(24):4745-8 · December 2003 with 24 Reads How we measure 'reads'Catalytic, Asymmetric ??-Chlorination of Acid Halides ketene dimers from acid halides journal of the americanArticle in Journal of the American Chemical ketene dimers from acid halides journal of the american available acid halides using cinchona alkaloid derivatives as catalysts and polychlorinated quinones as halogenating agents. ketene dimers from acid halides journal of the american 23][24][25][26][27 ketene dimers from acid halides journal of the american

Asymmetric synthesis of (S)- and (R)-malic acid from ketene dimers from acid halides journal of the american

May 01, 2002 · Catalytic, Asymmetric -Chlorination of Acid Halides. Journal of the American Chemical Society 2004 , 126 (13) , 4245-4255. DOI: 10.1021/ja039046t.A process for the production of ketene dimers. - Patent ketene dimers from acid halides journal of the americanIn the process at least 1.15 moles of tertiary amine is used per mole of fatty acid halide and the process is carried out in the substantial absence of an additional solvent, whereby the produced ketene dimer is obtained by stripping of the tertiary amine followed by separation of formed crystals of tertiary amine hydrogen halide by acid extraction.A process for the production of ketene dimers. - Patent ketene dimers from acid halides journal of the americanProduction of ketene dimers from fatty acid halides by reaction with tertiary amines whereby the tertiary amine is used both as a reactant and as a solvent/diluent. In the process at least 1.15 moles of tertiary amine is used per mole of fatty acid halide and the process is carried out in the substantial absence of an additional solvent ketene dimers from acid halides journal of the american

A process for the production of ketene dimers. - Patent ketene dimers from acid halides journal of the american

Production of ketene dimers from fatty acid halides by reaction with tertiary amines whereby the tertiary amine is used both as a reactant and as a solvent/diluent. In the process at least 1.15 moles of tertiary amine is used per mole of fatty acid halide and the process is carried out in the substantial absence of an additional solvent ketene dimers from acid halides journal of the americanKetene - an overview | ScienceDirect TopicsKetenes and ketene S,S-acetals displace ethylene from [Pt(PPh 3) 2 (C 2 H 4)] to form 2-bonded ketene complexes (reactions 643 and 644. 1498 An alternative preparation involves the displacement of oxygen from [Pt(PPh 3) 2 O 2]. 1499 Ketene dimer reacts with [Pt(PPh 3) 4], but in this case the product is not an 2-ketene complex of platinum ketene dimers from acid halides journal of the americanTheoretical Research on the Mechanism of the Dimerization ketene dimers from acid halides journal of the americanAlkyl ketene dimers can be prepared by reaction of acid halides with tertiary amines in inert organic solvents, and the main reaction is the dimerization reaction of alkyl ketene . It is generally believed that the reaction pathway involves, first of all, a reaction between acid halides and triethylamine to form a monoalkyl ketene intermediate:

Theoretical Research on the Mechanism of the Dimerization ketene dimers from acid halides journal of the american

Alkyl ketene dimers can be prepared by reaction of acid halides with tertiary amines in inert organic solvents, and the main reaction is the dimerization reaction of alkyl ketene . It is generally believed that the reaction pathway involves, first of all, a reaction between acid halides and triethylamine to form a monoalkyl ketene intermediate:(PDF) Theoretical Research on the Mechanism of the ketene dimers from acid halides journal of the american(alkyl ketene dimers, I) is an excellen t neutral sizing agent a n di sw i d e l yu s e di nt h ep a p e rm a k i n gi n d u s t r y[ ]. T raditionally rosin (acidic sizing) was used as a ketene dimers from acid halides journal of the american

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