- Migration of methyl groups between aliphatic amines in water
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Glycine undergoes spontaneous decarboxylation in dilute aqueous solution at elevated temperatures to form methylamine. During that process, we noticed the appearance of dimethylamine and trimethylamine in smaller amounts that increased gradually with time. These observations suggested the existence of disproportionation reactions of methylamines in water, for which there appears to be no direct precedent in the literature. Every member of the methylamine series is found to yield other members of the methylamine series. When the total concentration of amine was held constant and the rate of reaction was examined as a function of changing pH using the amine itself as the buffer, the initial rate of appearance of the products was found to reach a maximum when the conjugate acid and the conjugate base were present at equivalent concentrations. Near this equivalence point, the rate of reaction varied with pH as expected for a second-order reaction between the protonated and the unprotonated species. Under similar conditions, methyl groups were also found to migrate between the nitrogen atoms of N,N-dimethyl-1,3-propanediamine in a first-order process. With dimethylamine as a common acceptor, tetramethylammonium ion at ambient temperature. Copyright
- Callahan, Brian P.,Wolfenden, Richard
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- Reduction of Amides to Amines with Pinacolborane Catalyzed by Heterogeneous Lanthanum Catalyst La(CH2C6H4NMe2- o)3@SBA-15
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Hydroboration of amides is a useful synthetic strategy to access the corresponding amines. In this contribution, it was found that the supported lanthanum benzyl material La(CH2C6H4NMe2-o)3@SBA-15 was highly active for the hydroboration of primary, secondary, and tertiary amides to amines with pinacolborane. These reactions selectively produced target amines and showed good tolerance for functional groups such as -NO2, -halogen, and -CN, as well as heteroatoms such as S and O. This reduction procedure exhibited the recyclable and reusable property of heterogeneous catalysts and was applicable to gram-scale synthesis. The reaction mechanisms were proposed based on some control experiments and the previous literature. This is the first example of hydroborative reduction of amides to amines mediated by heterogeneous catalysts.
- Guo, Chenjun,Zhang, Fangcao,Yu, Chong,Luo, Yunjie
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supporting information
p. 13122 - 13135
(2021/08/31)
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- Manganese-Catalyzed Hydroborations with Broad Scope
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Reductive transformations of easily available oxidized matter are at the heart of synthetic manipulation and chemical valorization. The applications of catalytic hydrofunctionalization benefit from the use of liquid reducing agents and operationally facile setups. Metal-catalyzed hydroborations provide a highly prolific platform for reductive valorizations of stable C=X electrophiles. Here, we report an especially facile, broad-scope reduction of various functions including carbonyls, carboxylates, pyridines, carbodiimides, and carbonates under very mild conditions with the inexpensive pre-catalyst Mn(hmds)2. The reaction could be successfully applied to depolymerizations.
- Ghosh, Pradip,Jacobi von Wangelin, Axel
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supporting information
p. 16035 - 16043
(2021/06/16)
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- DRUG ELUTING POLYMER COMPOSED OF BIODEGRADABLE POLYMERS APPLIED TO SURFACE OF MEDICAL DEVICE
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This present invention relates to drug eluting polymers, including novel biodegradable drug eluting polymers, which are added to the surface of a medical device to treat device associated complications and to deliver drug locally around the device. Methods of making polymers, for example, drug-eluting polymers, polymer compositions, and materials used therewith also are provided. The drug eluting polymers are obtained from the polymerization of macromonomers made of a connecting moiety, a biodegradable moiety and a cross-linkable moiety that are liquids at a temperature of 10° C. to 40° C.
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- La[N(sime3)2]3-catalyzed deoxygenative reduction of amides with pinacolborane. scope and mechanism
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Tris[N,N-bis(trimethylsilyl)amide]lanthanum (LaNTMS) is an efficient and selective homogeneous catalyst for the deoxygenative reduction of tertiary and secondary amides with pinacolborane (HBpin) at mild temperatures (25-60 °C). The reaction, which yields amines and O(Bpin)2, tolerates nitro, halide, and amino functional groups well, and this amide reduction is completely selective, with the exclusion of both competing inter- and intramolecular alkene/alkyne hydroboration. Kinetic studies indicate that amide reduction obeys an unusual mixed-order rate law which is proposed to originate from saturation of the catalyst complex with HBpin. Kinetic and thermodynamic studies, isotopic labeling, and DFT calculations using energetic span analysis suggest the role of a [(Me3Si)2N]2La-OCHR(NR′2)[HBpin] active catalyst, and hydride transfer is proposed to be ligand-centered. These results add to the growing list of transformations that commercially available LaNTMS is competent to catalyze, further underscoring the value and versatility of lanthanide complexes in homogeneous catalysis.
- Barger, Christopher J.,Dicken, Rachel D.,Weidner, Victoria L.,Motta, Alessandro,Lohr, Tracy L.,Marks, Tobin J.
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supporting information
p. 8019 - 8028
(2020/05/27)
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- Frustrated Lewis Pair Catalyzed Hydrogenation of Amides: Halides as Active Lewis Base in the Metal-Free Hydrogen Activation
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A method for the metal-free reduction of carboxylic amides using oxalyl chloride as an activating agent and hydrogen as the final reductant is introduced. The reaction proceeds via the hydrogen splitting by B(2,6-F2-C6H3)3 in combination with chloride as the Lewis base. Density functional theory calculations support the unprecedented role of halides as active Lewis base components in the frustrated Lewis pair mediated hydrogen activation. The reaction displays broad substrate scope for tertiary benzoic acid amides and α-branched carboxamides.
- Sitte, Nikolai A.,Bursch, Markus,Grimme, Stefan,Paradies, Jan
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supporting information
p. 159 - 162
(2019/01/04)
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- Catalytic Hydrogenation for the Preparation of Amines from Amide Acetals, Ketene N,O-Acetals or Ester Imides
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The present invention relates to a process for the preparation of amines, comprising the following steps: Reaction of a (i) amide acetal of the general formula (I), or (ii) ketene N,O-acetal of the general formula (II), or (iii) ester imide of the general formula (III) with H2 in the presence of a hydrogenation catalyst, where catalyst and amide acetal or ketene N,O-acetal or ester imide are used in a molar ratio of from 1:10 to 1:100 000 and where a hydrogen pressure of from 0.1 bar to 200 bar is established and where a temperature in the range of from 0° C. to 250° C. is established.
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Paragraph 0150; 0152
(2016/10/04)
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- Selective Synthesis of Trimethylamine by Catalytic N-Methylation of Ammonia and Ammonium Chloride by utilizing Carbon Dioxide and Molecular Hydrogen
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The synthesis of trimethylamine (TMA) through a multicomponent combination of ammonia with carbon dioxide and molecular hydrogen by using a homogeneous ruthenium catalyst was explored. The use of [Ru(triphos)(tmm)] [triphos: 1,1,1-tris(diphenylphosphinomethyl)ethane, tmm: trimethylene methane] together with aluminum trifluoromethanesulfonate as a co-catalyst resulted in high ammonia conversion and excellent selectivity for TMA in organic solvents. Aqueous solutions of ammonium chloride were methylated almost quantitatively to the corresponding hydrochloride salt (i.e., TMA·HCl) in a biphasic solvent system by using the same Ru complex without the need for any co-catalyst.
- Beydoun, Kassem,Thenert, Katharina,Streng, Emilia S.,Brosinski, Sandra,Leitner, Walter,Klankermayer, Jürgen
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p. 135 - 138
(2016/01/26)
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- N-Methylation of Amines with Methanol at Room Temperature
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N-Methylation of amines with methanol proceeds at room temperature in the presence of a silver-loaded titanium dioxide (Ag/TiO2) photocatalyst under UV-vis light irradiation. This method allows facile synthesis/isolation of N-methylamines bearing various functional groups including N-benzyl, N-allyl, N-Boc, hydroxyl, ether, acetal, carboxamide, formamide, and olefin groups. (Chemical Presented)
- Tsarev, Vasily N.,Morioka, Yuna,Caner, Joaquim,Wang, Qing,Ushimaru, Richiro,Kudo, Akihiko,Naka, Hiroshi,Saito, Susumu
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supporting information
p. 2530 - 2533
(2015/05/27)
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- Magnesium-catalyzed mild reduction of tertiary and secondary amides to amines
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The first example of a catalytic hydroboration of amides for their deoxygenation to amines is reported. This transformation employs an earth-abundant magnesium-based catalyst. Tertiary and secondary amides are reduced to amines at room temperature in the presence of pinacolborane (HBpin) and catalytic amounts of ToMMgMe (ToM = tris(4,4-dimethyl-2-oxazolinyl)phenylborate). Catalyst initiation and speciation is complex in this system, as revealed by the effects of concentration and order of addition of the substrate and HBpin in the catalytic experiments. ToMMgH2Bpin, formed from ToMMgMe and HBpin, is ruled out as a possible catalytically relevant species by its reaction with N,N-dimethylbenzamide, which gives Me2NBpin and PhBpin through C-N and C-C bond cleavage pathways, respectively. In that reaction, the catalytic product benzyldimethylamine is formed in only low yield. Alternatively, the reaction of ToMMgMe and N,N-dimethylbenzamide slowly gives decomposition of ToMMgMe over 24 h, and this interaction is also ruled out as a catalytically relevant step. Together, these data suggest that catalytic activation of ToMMgMe requires both HBpin and amide, and ToMMgH2Bpin is not a catalytic intermediate. With information on catalyst activation in hand, tertiary amides are selectively reduced to amines in good yield when catalytic amounts of ToMMgMe are added to a mixture of amide and excess HBpin. In addition, secondary amides are reduced in the presence of 10 mol % ToMMgMe and 4 equiv of HBpin. Functional groups such as cyano, nitro, and azo remain intact under the mild reaction conditions. In addition, kinetic experiments and competition experiments indicate that B-H addition to amide C-O is fast, even faster than addition to ester C=O, and requires participation of the catalyst, whereas the turnover-limiting step of the catalyst is deoxygenation.
- Lampland, Nicole L.,Hovey, Megan,Mukherjee, Debabrata,Sadow, Aaron D.
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p. 4219 - 4226
(2015/11/11)
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- DENTAL ORAL COMPOSITION
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A dental composition for oral use, containing a phosphorylated saccharide (a), a polyphosphoric acid and/or a salt thereof (b), and a cationic bactericidal agent (c), wherein a ratio of a total amount of the phosphorylated saccharide (a) and the polyphosphoric acid and/or a salt thereof (b) contained to an amount of the cationic bactericidal agent (c) contained, i.e. {(a)+(b)}/(c), is from 0.05 to 20 in a weight ratio. The dental composition for oral use of the present invention can be suitably used for an oral cavity cleaning agent, including dentifrice agents such as a paste dentifrice agent, a powder dentifrice agent, and a liquid dentifrice agent, a mouse-wash agent, a troche, a tablet, a cream, an ointment, a bonding agent, a mouth spray, a coating agent to tooth surface or a dental prosthetic, a hypersensitive inhibitor, a therapeutic agent for periodontal diseases, that is applied to a periodontal pocket, wet tissue for oral cavity care, an oral refreshing agent, chewing gum, or a gargling agent, or the like.
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- METHOD FOR MANUFACTURING IONIC LIQUID CATALYSTS
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A method for manufacturing ionic liquid compositions by use of a two-step process which includes the contacting, under first reaction conditions, an mine compound with a hydrogen halide that is preferably in the gaseous form to provide a first reaction mixture. The first reaction mixture is then contacted, under second reaction conditions, with a metal halide compound to form the ionic liquid end-product.
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Page/Page column 11-12
(2008/06/13)
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- A solvent-free and formalin-free Eschweiler-Clarke methylation for amines
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Primary and secondary amines are N-methylated by a mixture of paraformaldehyde and oxalic acid dihydrate in good to excellent yields. The reaction proceeds without involvement of organic solvents and toxic formalin. Reaction temperatures of 100°C are required for the decomposition of oxalic acid into the intermediate formic acid which acts as the actual reductant. The reaction conditions have been optimized, and the mechanism has been elucidated by means of deuteration experiments.
- Rosenau, Thomas,Potthast, Antje,Roehrling, Juergen,Hofinger, Andreas,Sixta, Herbert,Kosma, Paul
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p. 457 - 466
(2007/10/03)
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- Hydrolysis of phosphotriesters: Determination of transition states in parallel reactions by heavy-atom isotope effects
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The remote label method was used to measure primary and secondary 18O isotope effects in the alkaline hydrolysis of O,O-diethylphosphorylcholine iodide (DEPC) and the primary 18O effect in the alkaline hydrolysis of O,O-diethyl-m-nitrobenzyl phosphate (DEmNBP). Both the leaving group of interest (choline or m-nitrobenzyl alcohol) and ethanol can be ejected during hydrolysis due to the similarity of their pK values. The heavy-atom isotope effects were measured by isotope ratio mass spectrometry. Parallel reaction and incomplete labeling corrections were made for both systems. DEPC has a primary 18O isotope effect of 1.041 ± 0.003 and a secondary 18O isotope effect of 1.033 ± 0.002. The primary 18O isotope effect for DEmNBP was 1.052 ± 0.003. These large effects suggest a highly associative transition state in which the nucleophile approaches very close to the phosphorus atom to eject the leaving group. The large values are also indicative of a large compression, or general movement, on the reaction coordinate.
- Anderson,Shim,Raushel,Cleland
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p. 9246 - 9253
(2007/10/03)
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- Cyclopropanesulfonyl Chloride: Its Mechanism of Hydrolysis and Reactions with Tertiary Amines in Organic Media
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Cyclopropanesulfonyl chloride (1) has been synthesized and its reactions examined to see if the three-membered ring leads to unusual reactions in either 1 or the corresponding sulfene, cyclopropanethione S,S-dioxide (2). pH-rate profiles, primary kinetic isotope effects (KIE's), and pH-product ratio experiments are in full agreement with mechanisms of hydrolysis of 1 like those of a simple alkanesulfonyl chlorides (J.Am.Chem.Soc.1992,114,1743-1749), specifically, (a) below pH 7.2 by SN2-S reaction with water and (b) above pH 7.3, elimination by hydroxide to form the sulfene (2) which is trapped by (i) water below pH 12.0 and (ii) hydroxide above pH 12.0.The products of the reaction of cyclopropanesulfonyl-1-d chloride (9) with triethylamine and 2-propanol in dichloromethane indicate that most of the reaction goes via 2; the analogous reaction with trimethylamine apparently proceeds by a direct formation of the sulfonylammonium chloride (14) which then yields the α-deuterated N,N-dimethyl sulfonamide (12, R=Me).The evident sulfene formation processes in the reaction of triethylamine with ethenesulfonyl, 2-propanesulfonyl, and cyclopropanesulfonyl chlorides show very low primary KIE's (1.5), pointing to highly product-like transition states.Reaction of 1 with an enamine (1-pyrrolidino-2-methylpropene, 20) in the presence of a base in either water or dichloromethane gave cyclopropanesulfonpyrrolidide (23) and an aldehyde adduct (24), but no four-membered cycloadduct (21).
- King, James F.,Lam, Joe Y. L.,Ferrazzi, Gabriele
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p. 1128 - 1135
(2007/10/02)
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- ASYMMETRIC NITROGEN - 70. GEMINAL SYSTEMS - 44. TRIALKOXYAMINES(ORTHONITRITES). SYNTHESIS AND PROPERTIES
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The chlorination of acyclic N,N-dialkoxyamines under the action of tert-BuOCl results in the formation of unstable N-chloro-N,N-dialkoxyamines wich in situ react with sodium methoxide to give previously unknown trialkoxyamines (orthonitrites).The properties of the N-chloro-N,N-dialkoxy- and trialkoxyamines have been demonstrated to be similar to those of their carbon analogues: dialkoxyalkylchlorides and orthoesters, respectively.
- Rudchenko, Vladimir F.,Ignatov, Sergei M.,Chervin, Ivan I.,Kostyanovsky, Remir G.
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p. 2233 - 2240
(2007/10/02)
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- AMINOLYSIS OF VINYLAMMONIUM SALTS. EFFECTS OF STRUCTURE AND MEDIUM
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The kinetics of the aminolysis of a series of vinylammonium salts ZCH=CHN+R3*X- were investigated in polar solvents and in water at 25 deg C.A quantitative assessment was made of the effect of the nature of the medium and the structure of activating group Z on the rate of the investigated processes.The aminolysis rate of the salts increases with increase in the donating characteristics of the solvent on account of the greater stabilization of the transition state compared with the initial state.Increase in the accepting characteristics of the medium leads to retardation of the process as a result of increase in the electrophilic solvation of the amine in the initial state.
- Kravchenko, V. V.,Popov, A. F.,Kotenko, A. A.
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p. 1332 - 1336
(2007/10/02)
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- Method for the preparation of persilylated carboxylic acid amides
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Disclosed is a method of preparing bis-trimethylsilylamides of carboxylic acids from the carboxylic acid amide by mixing two equivalents of trimethylchlorosilane and an excess of hexamethyldisilazane, heating the mixture to 40° to 80° C. and adding two equivalents of a tertiary amine as acid acceptor. The method results in substantially improved purity and yield of end product.
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- EFFECT OF THE STRUCTURE OF THE SUBSTRATE AND NUCLEOPHILE ON THE REACTION RATES OF ARYLSULFONYLVINYLTRIALKYLAMMONIUM SALTS WITH AMINES
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The kinetics of the reactions of arylsulfonylvinyltrialkylammonium salts with primary and secondary aliphatic amines in acetonitrile at 25 deg C were studied.On the basis of the low sensitivity of the reaction of β-(p-nitrophenylsulfonyl)vinyltriethylammonium chloride with alkylamines to the effect of the electronic and steric factors in the structure of the amines it was concluded that the transition state of the process is "looser" than in the reactions of the analogous substrates with a halogen as leaving group.The effect of the structure of the leaving trialkylammonium group on the rate of its substitution by the amino group was studied for the reaction of β-(p-nitrophenylsulfonyl)vinyltrialkylammonium chlorides with piperidine.The obtained data indicate that the process take place by an addition-elimination mechanism.
- Popov, A. F.,Kravchenko, V. V.,Kostenko, L. I.,Kotenko, A. A.,Kovach, N. A.
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p. 1915 - 1917
(2007/10/02)
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- Method of preparing tetrahalobenzene compounds, chemical intermediates used therein and certain of the compounds themselves
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Tetrahalobenzene compounds of the formula (I): STR1 in which X is independently chloro or, preferably, fluoro and Y is hydrogen or --N+ R3 A- in which each R is independently C1-4 alkyl and A is a radical capable of forming an anion A-, are prepared by (a) alkylating a compound of formula (II): STR2 or a salt thereof, to form a compound of formula (III): STR3 (b) treating the compound of formula (III) with a quaternizing agent of formula RA to form a compound of formula (IV): STR4 and (c) partially or completely reductively cleaving the compound of formula (IV) to replace one or both --N+ R3 A- groups by hydrogen. Compounds (I), in which Y is --N+ R3 A-, (III) and (IV) are novel. Compound (I) is useful in the synthesis of insecticides.
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- The reaction of bis(trifluoromethyl)phosphine with trimethylamine: New bis(phosphino)methanes, including an unusual triphosphine and a related tetraphosphine
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Trimethylamine dehydrofluorinates (CF3)2PH, forming (CH3)3NH2F2 and presumably CF3P=CF2, initiating a series of further reactions yielding P2(CF3
- Burg, Anton B.
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p. 3734 - 3740
(2008/10/08)
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- Effect of peroxides in the reaction of 2,4-dinitrochlorobenzene with triethylamine in dimethylformamide
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The effect of benzoyl and hydrogen peroxides in the reaction of 2,4-dinitrochlorbenzene with triethylamine in DMFA was studied.The increase in the formation rate of the reaction products (2,4-dinitrophenol and N,N-diethyl-2,4-dinitroaniline) is due to the reaction of the 2,4-dinitrochlorobenzene with the products from the reaction of triethylamine with the peroxides, i.e., diethylamine and benzoic acid in the case of benzoyl peroxide and triethylamine-N-oxide in the case of hydrogen peroxide.The oxidative nucleophilic substitution reaction of 2,4-dinitrochlorbenzene with triethylamine takes place in parallel.
- Ivanova, T. M.,Shein, S. M.
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p. 1055 - 1060
(2007/10/02)
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- The Mechanism of Photolysis of Some Benzyltrimethylammonium Salts in Water and in Alcohols
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Photolysis of a range of benzyltrimethylammonium and 3,5-dimethoxybenzyltimethylammonium salts in water or methanol at 253.7 nm gave typically benzyl alcohols (or benzyl methyl ethers), toluenes, bibenzyls and isomers, and di- and tri-methylammonium salts.By detailed sensitisation and quenching experiments it was established that, in the photolysis of benzyltrimethylammonium bromide in aqueous t-butyl alcohol, benzyl t-butyl ether, benzyl alcohol, and some toluene were produced by a singlet pathway and bibenzyl by a triplet pathway.A general mechanistic scheme for all the photolyses studied is thus suggested.
- Appleton, David C.,Bull, David C.,Givens, Richard S.,Lillis, Veronica,Kenna, James Mc,et al.
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- Carboxyl terminated polydienes
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Carboxyl terminated polymers prepared by reacting a cyclic anhydride with a liquid polymeric hydroxyl terminated polymer selected from polyethers, polydienes, and copolymers of the dienes with styrene or acrylonitrile in the presence of a catalyst selected from quaternary ammonium salts and from halogen acid salts of amines. The carboxyl terminated polymers can be used as flexibilizers in epoxy resins.
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- Certain pleuromutilins
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This invention relates to new pleuromutilins of the formula: STR1 wherein EITHER R1 is ethyl or vinyl, n is an integer from 2 to 5, X is sulphur, A group STR2 or a group =N-R4I, wherein Either Y and Z are both sulphur, or One of Y and Z is oxygen and the other is sulphur, and R4i is hydrogen or a group of the formula: STR3 wherein R1 is as defined above, EACH OF R2 and R3 is alkyl of 1 to 10 carbon atoms, or R2 and R3 together with the nitrogen atom form a heterocycle of 5 to 7 ring members containing one nitrogen atom or one nitrogen atom and a further hetero member selected from sulphur, oxygen and a group =N-R5I, wherein R5I is alkyl of 1 to 5 carbon atoms or hydroxyalkyl of 1 to 4 carbon atoms, or R2 and R3 together with the nitrogen atom form a piperazinyl radical, the second nitrogen atom of which is substituted by a radical R5II, whereby R5II is (acyloxy of 2 to 5 carbon atoms)alkyl of 1 to 4 carbon atoms or (benzoyloxy)alkyl of 1 to 4 carbon atoms, or Wherein R1 is as defined above, n is the number 2, R3 is alkyl of 1 to 10 carbon atoms, hydroxyalkyl of 1 to 4 carbon atoms, (acyloxy of 2 to 5 carbon atoms)alkyl of 1 to 4 carbon atoms or (benzoyloxy)alkyl of 1 to 4 carbon atoms, X is the group =N-R4II, and R2 together with R4II forms an ethylene bridge between both nitrogen atoms, And pharmaceutically acceptable acid addition salts and quaternary salts thereof. Processes for the preparation of such compounds are described. The compounds are antibiotics with an antibacterial effect.
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- Polymonoolefin quaternary ammonium salts of triethylenediamine
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High molecular weight N-hydrocarbyl-substituted quaternary ammonium salts in which the hydrocarbyl group has a molecular weight of from about 350-3000 such as a polybutene ammonium chloride are effective detergents and dispersants for gasoline and lubricating oils.
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- Lubricant additive
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High molecular weight N-hydrocarbyl-substituted quaternary ammonium salts in which the hydrocarbyl group has a molecular weight of from about 350-3000 such as a polybutene ammonium chloride are effective detergents and dispersants for gasoline and lubricating oils.
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- Control of insects and acarids with N-phosphinylamidines
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N-phosphinyl- or phosphinothioyl-amidines of the formula EQU1 wherein R1 represents methoxy or ethoxy R2 represents methyl, ethyl, propyl, n-pentyl, n-hexyl, allyl or propargyl each of R4 and R5 represents allyl or R4 and R5 form, with the nitrogen atom to which they are bound, the piperidino, ring, processes for their manufacture and their use for pest control.
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