- Pseudophase Approach to Reactivity in Microemulsions: Quantitative Explanation of the Kinetics of the Nitrosation of Amines by Alkyl Nitrides in AOT/Isooctane/Water Microemulsions
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The kinetics of the nitroso group transfer from 2-ethoxyethyl (EEN) and 2-bromoethyl (BEN) nitrit+e to the secondary amines piperazine (PIP), N-methylbenzylamine (NMBA), and morpholine (MOR) in bis(2-ethylhexyl) sulfosuccinate (AOT)/isooctane(iC8)/water microemulsions were determined.They are explained quantitatively in terms of a model in which the reagents are distributed among the aqueous, organic, and AOT film surfactant, with the aqueous pseudophase and the surfactant film as the losi of the reaction.
- Garcia-Rio, L.,Leis, J. R.,Mejuto, J. C.
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Read Online
- Lignin-fueled photoelectrochemical platform for light-driven redox biotransformation
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The valorization of lignin has significant potential in producing commodity chemicals and fuels from renewable resources. However, the catalytic degradation of lignin is kinetically challenging and often requires noble metal catalysts to be used under harsh and toxic conditions. Here, we report the bias-free, solar reformation of lignin coupled with redox biotransformation in a tandem structure of a BiVO4 photoanode and perovskite photovoltaic. The tandem structure compensates for the potential gap between lignin oxidation and biocatalytic reduction through artificial Z-schematic absorption. We found that the BiVO4-catalyzed photoelectrochemical oxidation of lignin facilitated the fragmentation of higher molecular weight lignin into smaller carboxylated aliphatic and aromatic acids. Lignin oxidation induced photocurrent generation at the photoanode, which enabled efficient electroenzymatic reactions at the cathode. This study successfully demonstrates the oxidative valorization of lignin as well as biocatalytic reductions (e.g., CO2-to-formate and α-ketoglutarate-to-l-glutamate) in an unbiased biocatalytic PEC platform, which provides a new strategic approach for photo-biocatalysis using naturally abundant renewable resources.
- Boonmongkolras, Passarut,Choi, Eun-Gyu,Han, Seunghyun,Kim, Jinhyun,Kim, Kayoung,Kim, Yong Hwan,Lee, Sahng Ha,Lee, Yang Woo,Park, Chan Beum,Shin, Byungha,Trang, Nguyen Vu Thien,Wang, Ding
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supporting information
p. 5151 - 5160
(2020/08/25)
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- Selective synthesis of dimethoxyethane via directly catalytic etherification of crude ethylene glycol
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Etherification of ethylene glycol with methanol provides a sustainable route for the production of widely used dimethoxyethane; dimethoxyethane is a green solvent and reagent that is applied in batteries and used as a potential diesel fuel additive. SAPO-34 zeolite was found to be an efficient and highly selective catalyst for this etherification via a continuous flow experiment. It achieved up to 79.4% selectivity for dimethoxyethane with around 96.7% of conversion. The relationship of the catalyst's structure and the dimethoxyethane selectivity was established via control experiments. The results indicated that the pore structure of SAPO-34 effectively limited the formation of 1,4-dioxane from activated ethylene glycol, enhanced the reaction of the activated methanol with ethylene glycol in priority, and thus resulted in high selectivity for the desired products. The continuous flow technology used in the study could efficiently promote the complete etherification of EG with methanol to maintain high selectivity for dimethoxyethane.
- Yu, Weiqiang,Lu, Fang,Huang, Qianqian,Lu, Rui,Chen, Shuai,Xu, Jie
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supporting information
p. 3327 - 3333
(2017/07/28)
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- Reactivity of [WCl6] with Ethers: A Joint Computational, Spectroscopic and Crystallographic Study
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The reactions of [WCl6] with a series of ethers have been performed in chlorinated solvent and elucidated by means of analytical, spectroscopic and DFT methods. The addition of tetrahydropyran (thp) or 1,4-dioxane to [WCl6] resulted in the reversible formation of the adducts WCl6···L [L = thp (1a), 1,4-dioxane (1b)], detected in solution by NMR spectroscopy. The reaction of [WCl6] with thp in a molar ratio of 1:2 in chloroform at reflux afforded [WOCl4(thp)] (2a), which was isolated in 51 % yield. [WOCl4(OMe2)] (2b) and [WOCl3(OMe2)2] (3a) were isolated in yields of 53 and 18 %, respectively, from the reaction of [WCl6] with an excess of dimethyl ether. [WOCl3(OEt2)2] (3b) was the only identified metal compound produced from the reaction of [WCl6] and OEt2(1:2 molar ratio). According to NMR studies, the oxide ligand in 2a,b and 3a,b was generated by double C–O bond cleavage involving one equivalent of organic reactant. The 1:1 reaction of [WCl6] with 1,2-diethoxyethane led to [WCl5(κ1-OCH2CH2OEt)] (4) and a minor amount of [WCl4(κ2-EtOCH2CH2OEt)] (5). The aryl oxide compound [WCl5(OPh)] (6) was prepared in 62 % yield from the reaction of [WCl6] and anisole by selective Csp3–O bond activation. The prolonged heating of a mixture of [WCl6] and diphenyl ether in 1,2-dichloroethane led to the isolation of the WVcomplex [WCl5(OPh2)] (7). The molecular structures of 2a and 3a were ascertained by X-ray diffraction.
- Bortoluzzi, Marco,Marchetti, Fabio,Pampaloni, Guido,Zacchini, Stefano
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p. 3169 - 3177
(2016/07/14)
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- Ruthenium bipyridyl tethered porous organosilica: A versatile, durable and reusable heterogeneous photocatalyst
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A versatile heterogeneous photocatalysis protocol was developed by using ruthenium bipyridyl tethered porous organosilica (Ru-POS). The versatility of the Ru-POS catalyst in organo-photocatalysis was explored by (i) oxidative aromatization of Hantzsch ester, (ii) reductive dehalogenation of alkyl halides, and (iii) functional group interconversion (FGI) of alcohols to alkyl halides. This journal is
- Jana, Avijit,Mondal, John,Borah, Parijat,Mondal, Sujan,Bhaumik, Asim,Zhao, Yanli
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supporting information
p. 10746 - 10749
(2015/06/30)
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- Highly efficient synthesis of diethyl carbonate via one-pot reaction from carbon dioxide, epoxides and ethanol over KI-based binary catalyst system
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The synthesis of diethyl carbonate (DEC) directly from carbon dioxide, ethylene oxide (EO), and ethanol via one-pot reaction is reported for the first time. The effects of catalyst species and reaction variables on the synthetic performance of DEC were systematically studied. The integration of easily available KI and sodium ethoxide as homogeneous binary catalyst system was found to be very active for the one-pot reaction, and 63.6% of the DEC yield could be achieved under relatively mild reaction conditions (443 K, 3 MPa CO2 initial pressure, 2 h). The byproduct of 2-ethoxyethanol, which is predominantly formed via alcoholysis of EO by ethanol through ring-opening reaction, was produced with small amount (rHmθ=-19.70 a?€S?a?€S?kcal/mol2 and ethanol, the involvement of EO facilitates the formation of DEC, simultaneously with glycol produced. This strategy could also be successfully expanded to terminal epoxide substrates. Furthermore, a possible mechanism of the reaction was proposed on the basis of experimental results. This method provides a highly effective way to produce DEC via directly chemical utilization of CO2 and shows promising application in the manufacture of diethyl carbonate on an industrial scale.
- Wang, Liguo,Li, Huiquan,Xin, Shumin,He, Peng,Cao, Yan,Li, Fengjiao,Hou, Xinjuan
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- A procedure for the preparation of Ti-Beta zeolites for catalytic epoxidation with hydrogen peroxide
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Ti-Beta zeolite has been successfully prepared via a reproducible and scalable two-step post-synthesis strategy, which consists of creating vacant T sites with associated silanol groups by dealumination of H-Beta and subsequent dry impregnation of the resulting Si-Beta with titanocene dichloride. The mechanism of Ti incorporation into the framework of Beta is investigated by diffuse reflectance infrared Fourier transform (DRIFT) and multinuclear solid-state nuclear magnetic resonance (SSNMR) spectroscopy. Characterization results obtained from diffuse reflectance ultraviolet-visible (UV-vis) and X-ray photoelectron spectroscopy (XPS) reveal that the majority of incorporated Ti species exist in the form of isolated tetrahedrally coordinated Ti(iv) in the zeolite framework while a minority exists in the form of isolated octahedrally coordinated Ti(vi) at framework or extra-framework positions. The obtained Ti-Beta zeolites are highly active and selective catalysts for the epoxidation of unsaturated ketones, e.g. 2-cyclohexen-1-one, with hydrogen peroxide as an oxidant. A quasilinear correlation between the epoxidation rate and the number of framework Ti(iv) species could be drawn evidencing that these Ti(iv) species are responsible for the epoxidation activity of the Ti-Beta zeolites under study. The impact of preparation parameters and reaction conditions on the catalytic performances of the Ti-Beta zeolites in the epoxidation of unsaturated organic compounds with hydrogen peroxide is discussed in detail. the Partner Organisations 2014.
- Tang, Bo,Dai, Weili,Sun, Xiaoming,Guan, Naijia,Li, Landong,Hunger, Michael
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p. 2281 - 2291
(2014/04/17)
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- Catalytic Conversion Of Alcohols To Aldehydes Or Ketones
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Catalytic reactions are taught using air or oxygen for oxidative chemical conversion of primary alcohols to aldehydes and for secondary alcohols to ketones in a vapor phase at ambient pressure. The catalytic process converts ethanol to acetaldehyde, n-propanol to propionaldehyde, 2-propanol to acetone, and other alcohols to aldehydes and ketones. The catalysts are based on molecular strings of di-, tri- and/or poly-groups of transition metal complexes possessing a specific degree of symmetry. Laboratory results have demonstrated [vanadium (II)]2, [chromium (II)]2, [manganese (II)]2, [cobalt (II)]2 oxalate and symmetric transition metal catalysts to be effective for oxidative catalytic conversion of primary alcohols to products comprising related aldehydes and secondary alcohols to products comprising ketones.
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Paragraph 0021
(2014/03/21)
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- COMPOSITIONS, SYNTHESIS, AND METHODS OF USING PHENYLCYCLOALKYLMETHYLAMINE DERIVATIVES
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The present invention provides novel phenylcycloalkylmethylamme derivatives, and methods of preparing phenylcycloalkylmethylamme derivatives. The present invention also provides methods of using phenylcycloalkylmethylamme derivatives and compositions of phenylcycloalkylmethylamme derivatives. The pharmaceutical compositions of the compounds of the present invention can be used for treating and/or preventing obesity and obesity related co- morbid indications and depression and depression related co-morbid indications.
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Page/Page column 54
(2013/07/19)
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- Production of dimethyl carbonate from ethylene carbonate and methanol using immobilized ionic liquids on MCM-41
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Ionic liquids on ordered mesoporous silica were prepared and their catalytic performance in the synthesis of dimethyl carbonate (DMC) was investigated. The ionic liquids were immobilized on chloropropyl-functionalized MCM-41 (CP-MS41) through the quaternization of trialkylamines. The supported ionic liquids were proven to be an effective heterogeneous catalyst for the synthesis of DMC from transesterification of ethylene carbonate (EC) with methanol. The immobilized quaternary ammonium salt (QCl-MS41) catalysts with longer alkyl chains showed higher EC conversion and turnover number (TON). Higher temperatures and longer reaction times were favorable for the reactivity of QCl-MS41. However, carbon dioxide pressure showed a maximum for catalytic activity. The catalyst can be reused for reactions in up to three consecutive runs with only a slight decrease in catalytic activity.
- Kim, Dong-Woo,Lim, Dong-Ok,Cho, Deug-Hee,Koh, Jae-Cheon,Park, Dae-Won
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experimental part
p. 556 - 560
(2012/02/03)
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- Further insights into the chemistry of niobium and tantalum pentahalides with 1,2-dialkoxyalkanes: Synthesis of bromo- and iodoalkoxides, spectroscopic and computational studies
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The room temperature reactions of a series of 1,2-dialkoxyalkanes ROCH 2CH(R′)OR′′ with MX5 (M = Nb, Ta; X = Br, I) in 1:1 ratio result in single C-O bond cleavage and high-yield formation of the halo-alkoxides MBr4[κ2-OCH 2CH(R′)OR′′] or [NbI4{κ 1-OCH2CH(R′)OR′′}]2, and equimolar amounts of the corresponding alkyl halides RX. The reaction of NbBr5 with 1,2-dimethoxyethane, dme, proceeds with preliminary formation of the ionic species [NbBr4(κ2-dme) (κ1-dme)][NbBr6], 3b, which has been identified by solution NMR at low temperature and conductivity analyses. The gas-phase structure of 3b has been optimized by DFT calculations, confirming that the dme ligands adopt bidentate and monodentate coordination, respectively. Although the formation of NbOBr3(dme), 4b, 1,4-dioxane and MeBr from NbBr 5/dme (ratio 1:2) is an exoergonic process (calculated ΔGr° = -115.96 kcal mol-1), it is inhibited at room temperature. High temperature conditions enhance the production of 1,4-dioxane at the expense of selectivity. The dinuclear species NbOBr3(dme)NbBr5 (Nb-O-Nb), 5b, (X-ray) has been isolated in modest yield as byproduct of the room temperature reaction of NbBr5 with dme. In general, the 1:2 molar reactions of NbX5 (X = Br, I) with ROCH2CH(R′) OR′′ occur with the exclusion of nearly one equivalent of organic reactant.
- Bini, Riccardo,Marchetti, Fabio,Pampaloni, Guido,Zacchini, Stefano
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experimental part
p. 1412 - 1419
(2011/06/22)
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- Organometallic Complex, and Light-Emitting Element, Light-Emitting Device, Electronic Device, and Lighting Device Using the Organometallic Complex
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To provide a novel organometallic complex capable of emitting phosphorescence by using an organic compound with which a variety of derivatives can be easily synthesized as a ligand. In addition, to provide an organometallic complex which exhibits red emission. To provide an organometallic complex formed by ortho-metalation of an m-alkoxyphenyl pyrazine derivative represented by General Formula (G0) below with respect to an ion of a metal belonging to Group 9 or Group 10. In addition, to provide an organometallic complex which exhibits red emission formed by ortho-metalation of an m-alkoxyphenyl pyrazine derivative represented by General Formula (G0) below with respect to an ion of a metal belonging to Group 9 or Group 10.
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- PROCESS FOR PREPARING AN ALKOXYLATED ALCOHOL OR PHENOL
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Process for preparing an alkoxylated alcohol comprising reacting a starting monohydroxy alcohol selected from secondary alcohols, tertiary alcohols and mixtures thereof with an alkylene oxide in the presence of hydrogen fluoride and a boron-containing compound comprising at least one B-O bond. The alcohol may also be a primary monohydroxy alcohol when the boron containing compound is boric acid or boric acid anhydride or a mixture thereof, or may be a primary mono hydroxy alcohol, except a C14/C15 alcohol when reacted with ethylene oxide in the presence of HF and trimethyl borate. A phenol may be alkoxylated in the same way instead of the mono-hydroxyalcohol.
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Page/Page column 19-20
(2008/06/13)
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- Isergonic relationship in the acid-catalyzed hydrolysis of carboxylic esters with hydrogen-bonding capability
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The average value of the enthalpies of activation for the acid-catalyzed hydrolyses of ethyl 2-hydroxypropanoate and five acetate esters with hydrogen bonding capability is 57 ± 7 kJ mol-1 (p = 0.05). This value is 11 kJ mol-1 lower than the mean observed for primary and secondary alkyl acetates and ethyl alkanoates, measured in water and in mixtures of water with organic solvent with high water content. The difference is attributed to tighter transition-state complex hydration via hydrogen bonding, relative to reactant ester species. Enthalpy-entropy compensation with an isokinetic temperature of 346 K was found to be valid at p 0.05, a value typical for solvent-mediated kinetic effects. Copyright
- Mata-Segreda, Julio F.
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p. 567 - 571
(2007/10/03)
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- Transetherification of organosilicon amines with cellosolve and trimethylsilanol
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Kinetics of transetherification of (3-aminopropyl)trimethoxysilane, [3-N-(2-aminoethyl)amino-propyl]trimethoxysilane, and (3-aminopropyl) triethoxysilana with Cellosolve and trimethylsilanol were studied. The example of [3-N-(2-aminoethyl)aminopropyl]trim
- Kovyazin,Nikitin,Kopylov,Sokol'skaya
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p. 1383 - 1387
(2007/10/03)
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- Synthesis and antiproliferative activity of alkylphosphocholines
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Alkylphosphocholines (APC) with one or more methylene groups in the alkyl chain replaced by oxygen atoms or carbonyl groups, or both have been assembled modularly using ω-diols as central building blocks. Out of 25 new compounds of this kind, 11 were evaluated for their antiproliferative activity on four cell lines and compared with miltefosine to evaluate their hemolytic activity (HA) and cytotoxicity on non-tumoral cells (MT2), used as markers of adverse effects. Compound 13 was more active on cancer cell lines than on non-tumoral cells and the data were similar for MTT and thymidine incorporation assays. It had less HA than miltefosine. Compound 13 could therefore be a candidate for the preparation of compounds with higher cytotoxicity on cancer cells and lower general toxicity.
- Agresta, Mandy,D'Arrigo, Paola,Fasoli, Ezio,Losi, Daniele,Pedrocchi-Fantoni, Giuseppe,Riva, Simona,Servi, Stefano,Tessaro, Davide
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p. 201 - 210
(2007/10/03)
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- The mechanism of the metal ion promoted cleavage of RNa phosphodiester bonds involves a general acid catalysis by the metal aquo ion on the departure of the leaving group
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A series of uridine 3′-alkyl phosphates and 3′-aryl phosphates were synthesised and their cleavage was studied in the presence of Zn2+ aquo ions. A βlg value was determined for the Zn2+ promoted cleavage of both types of compounds. Comparison of the results obtained to those reported previously for the cleavage of the same substrates in the absence of metal ion catalysts suggests that the alkyl leaving group departs as an alcohol in the presence of metal ion catalysts. Furthermore, metal ion catalysts seem to enhance the departure. The aryl leaving group, in contrast, departs as an oxyanion.
- Mikkola, Satu,Stenman, Eeva,Nurmi, Kirsi,Yousefi-Salakdeh, Esmail,Stroemberg, Roger,Loennberg, Harri
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p. 1619 - 1625
(2007/10/03)
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- Cyclodextrins as enzyme models in nitrosation and in acid-base- catalyzed reactions of alkyl nitrites
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The widely studied cyclodextrin-mediated reactions of esters but not those of alkyl nitrites, together with the marked differences between the chemistry of esters and alkyl nitrites, prompted us to investigate the influence of β-cyclodextrin (β-CD) on the reactions of alkyl nitrites. Due to the particular characteristics of alkyl nitrite reactions, the system β- cyclodextrin-alkyl nitrites allows us to explore cyclodextrin's behavior under several experimental conditions, contrary to the case of esters. Therefore, general acid-base-catalyzed hydrolysis and nitrosation of amines by alkyl nitrites are studied. Alkyl nitrites of a particular structure have been chosen to clearly evidence the mimicry of enzyme catalysis by β-CD. Addition of β-CD strongly inhibits the acid hydrolysis of alkyl nitrites (a very fast reaction in water), except in the case of ethoxyethyl nitrite, where no effect is detected. The retardation of the reaction is attributed to a separation of the reagents: β-CD and alkyl nitrites form host-guest 1:1 inclusion complexes, but simple cations, such as H3O+ in the present case, did not prove to include into the β-CD cavity. In fact, at constant β-CD concentrations, addition of dodecyltrimethylammonium bromide monomers (DTABr), which strongly compete with alkyl nitrites for the hydrophobic β- CD cavity and, thus, expel the alkyl nitrites, catalyzes the reaction. On the contrary, in alkaline medium, when a secondary hydroxy group of β-CD is ionized, addition of β-CD to the reaction medium strongly catalyzes the basic hydrolysis of alkyl nitrites (an extremely slow reaction in water). The degree of catalysis depends on the alkyl nitrite structure, varying from a factor higher than 100 in the case of 3-phenyl-1-propyl nitrite, to 0 (no reaction is observed) in the case of 2-phenyl-2-propyl nitrite. The effective molarities calculated for the catalysis evidence a base-catalyzed mechanism for the reaction. The strong catalysis observed with 1-phenyl-1-propyl nitrite upon the addition of DTABr is indicative of an example of allosteric activation. Finally, the nitrosation of pyrrolidine, piperidine, and cyclohexylamine by ethoxyethyl nitrite is slightly catalyzed by the presence of β-cyclodextrin. The degree of the observed catalysis depends on both the amine concentration and the structure.
- Iglesias, Emilia
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p. 13057 - 13069
(2007/10/03)
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- Kinetics of the Reaction of Malononitrile with Alkyl Nitrites
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The reaction of malononitrile with aliphatic alkyl nitrites in aqueous basic media to give the corresponding oxime product HON=C(CN)2 goes through a mechanism involving a rate-limiting reaction between the alkyl nitrite and the carbanion CH(CN)2.
- Iglesias, Emilia
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- Nucleophilic Reactivity towards 'Normal' and Ambidendate Electrophiles Bearing the Nitroso Group
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Bimolecular rate constants for the reactions of N-methyl-N-nitrosotoluene-p-sulfonamide (MNTS) and 2-ethoxyethyl nitrite (EEN) with oxygen nucleophiles -, CF3CH2O-, HO2-, CH3(CO)NHO- and ClO->, sulfur nucleophiles (SO32-, SCN-, thiourea, cysteine, S2O32- and HS-) and I- have been determined.For MNTS, 'soft' nucleophiles react at the nitroso group, whereas 'hard' nucleophiles react at least in part at the sulfonyl group.A discussion on the validity of nucleophilicity scales (N+ and n) is carried out and clearly for soft nucleophiles (N- and S- nucleophiles and I-) there is a good correlation with N+ with a slope close to 1 which implies a frontier orbital controlled reaction and a markedly diradicaloid transition state.For reactions at the sulfonyl group (O-nucleophiles), nucleophilic reactivity is better explained using the n scale which can be rationalized in terms of a larger electrostatic contribution to the interaction energy.
- Leis, J. Ramon,Pena, M. Elena,Rios, Ana M.
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p. 587 - 594
(2007/10/02)
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- Triphendioxazine dyestuffs
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The novel triphendioxazine dyestuffs of the formula STR1 in which the substituents R, R', T1, T2, X, Y and n have the meanings given in the description are highly suitable for the dyeing and printing of cellulose-containing or amido-containing material.
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- Reactivity of Nucleophilic Nitrogen Compounds towards the Nitroso Group
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We discuss the reactivity of 43 nucleophilic nitrogen compounds towards the nitroso group of N-methyl-N-nitrosotoluene-p-sulfonamide (MNTS), and in some cases with alkyl nitrites.The series of nucleophiles considered is structurally very varied, includes members exhibiting the alpha effect, and covers 8 pKa units and a range of reactivities of almost five orders of magnitude.The values of solvent isotope effects and activation parameters have been measured and throw light on the structure of the transition states involved.Reactivities do not correlate well with thebasicity of the nucleophile, largely owing to the behaviour of primary amines, ammonia and nucleophiles with an alpha effect.Application of the curve crossing model suggests a relationship with vertical ionization potentials.The relationship with Ritchie's N+ scale is discussed, and interesting correlations with the reactivities of the same nucleophiles in various other chemical processes are noted.
- Garcia-Rio, Luis,Iglesias, Emilia,Leis, J. Ramon,Pena, M. Elena,Rios, Ana
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- A Novel Route to Peroxynitrite Anion
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HOO- is nitrosated efficiently and directly by alkyl nitrites in basic media to yield quantitative amounts of peroxynitrite.
- Leis, J. Ramon,Pena, M. Elena,Rios, Ana
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p. 1298 - 1299
(2007/10/02)
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- Evidence for Concerted Acid Hydrolysis of Alkyl Nitrites
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The results of studying the acid hydrolysis of methyl, ethyl, isopropyl, butyl, tert-butyl, pentyl, 2-bromoethyl, 2-chloroethyl and 2-ethoxyethyl nitrites in water show that the reaction is not, as widely accepted in the literature, catalysed by nucleophiles (Cl-, Br-, etc.), but is however subject to general acid catalysis.These findings, and the observed values of the solvent isotope effect, suggest that the substrate is protonated in the rate-controlling step of the reaction.Further, the relative reactivities of the various substrates investigated suggest a concerted mechanism in which the proton transfer occurs concurrently with the breaking of the O-N bond via a slightly imbalanced transition state.
- Iglesias, Emilia,Garcia-Rio, Luis,Leis J. Ramon,Pena, M. Elena,Williams, D. Lyn H.
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p. 1673 - 1679
(2007/10/02)
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- Tinctorial composition for keratin fibres, based on nitrated benzene dyestuffs
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A process for dyeing keratin fibres is disclosed which involved applying: (a) at least one dyestuff of the formula: STR1 in which R1 and R2 independently designate hydrogen, amino, alkylamino, --NH--aliphatic--(X)m, dialkylamino or --N--(aliphatic-(X)m)2, R3 designates hydrogen, OH, alkoxy or --O--aliphatic-(X)m "aliphatic" designates an aliphatic radical having 2 to 4 free valencies, m designates an integer from 1 to 3 such that if m=1 X represents OH, Cl, OCH3 or OCH2 CH2 OH, or, if m designates 2 or 3, X designates OH, and R4 designates hydrogen, alkyl or halogen, with the proviso that at least one of R1, R2 and R3 is other than hydrogen, and that, if R1 and R2 are both other than hydrogen, R3 designates hydrogen, (b) at least one dyestuff of the formula: STR2 in which R5 designates hydrogen, amino, aminoalkyl, NH-aliphatic-(X)m, N-(alkyl)2, N-(aliphatic(X)m)2, or NHCH2 CH2 NH2, R6 designates hydrogen, OH, alkoxy, O-aliphatic(X)m or O(CH2)n NH2, R7 designates hydrogen, alkyl or halogen, A designates-Y-(CH2)--n, --OCH2 CHOH--CH2 -- or STR3 where R8 designates hydrogen or methyl, Y designates oxygen or --NH-- and n is an integer from 2 to 4, and m "aliphatic" and X are as defined above, with the proviso that, if Y designates --NH-- and R6 is other than hydrogen, R5 designates hydrogen, and, if Y is an oxygen atom, R6 designates hydrogen, the shade and chromaticity of the color obtained with the dyestuff(s) of formula (I) and the shade and chromaticity of the color obtained with the dyestuff(s) of formula (II) being such that ΔH+ΔC is less than or equal to 4.5
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- Ruthenium-cobalt carbonyl metal cluster catalysts for the dealkoxyhydroxymethylation of acetals to form glycol ethers
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The ruthenium-cobalt carbonyl metal cluster catalyst Co2 Ru(CO)11 effectively catalyzes the dealkoxyhydroxymethylation of aldehyde acetals to form glycol monoethers. Methylal, for example, may be reacted with syngas, i.e., CO and H2, in the presence of this ruthenium-cobalt cluster catalyst to form the monomethyl ether of ethylene glycol.
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- Catalysts for alkoxylation reactions
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Catalysts producing a sharply peaked alkoxylation distribution during the alkoxylation of organic materials comprise mixtures of BF3 and metal alkyls or metal alkoxides, SiF4 and metal alkyls or metal alkoxides, or mixtures of these catalysts.
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- Methods of alkoxylation
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Catalysts comprising mixtures of HF and metal alkoxides and mixed metal alkoxides produce a sharply peaked alkoxylation distribution during the alkoxylation of organic materials.
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- Fibre-reactive dyes, containing both chloro and fluoro triazine radicals
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Fibre-reactive dyes of the formula STR1 wherein D is the radical of a benzene or naphthalene azo dye which contains sulpho groups, each of R1, R2 and R3 is a hydrogen atom, B is an arylene group and A is an amino group.
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- Catalysts for alkoxylation reactions
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Catalysts and a method of using said catalysts for the alkoxylation of a variety of materials is disclosed. Catalysts so described produce alkoxylates having a very sharp alkoxylate distribution. The catalysts are supported and unsupported dialkoxy and dialkyl metal fluorides and halides and alkyl metal difluorides and dihalides.
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- TRANSFORMATION OF 1,3-DIOXACYCLOALKANES BY THE ACTION OF DIETHYLALUMINUM HYDRIDE AND TRIETHYLALUMINUM.
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There are reports on the reduction of ethylene glycol acetals and ketals by aluminum hydrides to the corresponding monoethers. Considering that these compounds find wide application as solvents, plasticizers, and perfume ingredients, it was of interest to study the possibility of a selective hydrogenation of different 1,3-dioxacycloalkanes by industrial grade mixtures of diethylaluminum hydride and triethylaluminum. According to the data obtained for the reactions with cyclic acetals, triethylaluminum is 1. 5-2 times more active than diethylaluminum hydride. The activities of the five-membered ring acetals and ketals in the reduction and alkylation processes are similar; 2-phenyl-1, 3-dioxolane has the highest reactivity. Thus, 2-mono- and 2,2-disubstituted 1,3-dioxacyclanes form monoethers of the correepsponding diols by the action of diethylaluminum hydride and triethylauminum. In the case of triethylaluminum, ethylation of the carbon atom adjacent to the two oxygen atoms takes place.
- Volkov,Kravets,Zlot-skii,Rakhmankulov
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p. 1419 - 1423
(2007/10/02)
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- Process for producing ether compounds by catalytic hydrogenolysis
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In a process for producing an ether compound by the catalytic hydrogenolysis of an acetal compound in the presence of a catalyst, the improvement wherein an acetal compound of the following formula (2) STR1 wherein R represents a hydrogen atom or a lower alkoxy group, Y represents an alkylene group having 2 to 12 carbon atoms, n represents a positive number of from 1 to 6, the two groups R(YO)n may, together with the carbon atom to which they are bonded, represent a 1,3-dioxolane ring, and R1 and R2, independently from each other, represent a hydrogen atom or a C1 -C6 alkyl group, provided that at least one of R1 and R2 represents a hydrogen atom, is catalytically hydrogenolyzed in the presence of a palladium catalyst on a carbon carrier in the absence of an acid substance added, thereby to form an ether compound of the following formula (1) wherein R, R1, R2, Y and n are as defined.
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- SULFATION OF ALCOHOLS OF DIFFERENT STRUCTURES WITH CONCENTRATED SULFURIC ACID.
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The authors report the results of a study of the applicability of these relationships to the whole series of aliphatic alcohols including industrial products. The concentration equilibrium constants of the reactions of these alcohols with 99. 5 mass % sulfuric acid are determined at 32. 5 degree , and it is shown that all the higher alcohols can be characterized by the same equilibrium constant, 3. 1 plus or minus 0. 5, which can therefore be recommended for practical calculations. The equilibrium constants were calculated from the rate constants of the forward and reverse reactions. It is shown that they depend on the relative basicities of sulfuric acid and monoalkyl sulfates.
- Savelyanov,Yakushin
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p. 1527 - 1531
(2007/10/02)
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- Ethylene Glycol from Synthesis Gas via Bimetallic Catalysis
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Ethylene glycol and its monoalkyl ether derivatives have been prepared from synthesis gas through the application of an unique ruthenium-rhodium 'melt' catalyst system.
- Knifton, John F.
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p. 729 - 730
(2007/10/02)
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- Hydrolysis, Nitrosyl Exchange, and Synthesis of Alkyl Nitrites
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Alkyl nitrites undergo relatively slow hydrolysis in phosphate-buffered aqueous media under neutral conditions with small but significant dependence of reactivity on structure.However, rapid nitrosyl exchange with alcohols is observed, and equilibrium constants for this transformation exhibit remarkable correlation with equilibrium constants for nitrosyl exchange of alcohols with nitrosyl chloride and with nitrous acid. tert-Butyl nitrite has the greatest driving force for nitrosyl transfer among the 12 alkyl nitrites examined, and this capability is used for the synthesis of alkyl nitrites derived from steroidal alcohols and of alkyl thionitrites.
- Doyle, Michael P.,Terpstra, Jan W.,Pickering, Ruth A.,LePoire, Diane M.
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p. 3379 - 3382
(2007/10/02)
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- Hydroisomerization of 1,3-Dioxacycloalkanes to Esters on Platinum. The Role of Hydrogen in the Isomerization.
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Experiments show that the isomerization of 1,3-dioxacycloalkanes to esters proceeds only in the presence of hydrogen, and the selectivity for ester formation can be > 90percent with optimum hydrogen coverage; new data are reported relevant to the mechanism of ester formation and the generalization of the hydroisomerization.
- Bartok, Mihaly,Czombos, Jozsef
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p. 978 - 979
(2007/10/02)
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- Isomerization and Hydrogenolysis of 1,3-Dioxacycloalkanes on Metal Catalysts
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The isomerization of 5-, 6-, and 7-membered 1,3-dioxacycloalkanes to esters on various metal catalysts is reported, the hydrogenolysis pattern for this type of compound is determined, and a new reaction mechanism is proposed to interpret these catalytic processes.
- Bartok, Mihaly,Czombos, Jozsef
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p. 106 - 108
(2007/10/02)
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- Preparation of gamma-pyrones
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2-METHYL-3-HYDROXY-4H-pyran-4-one is prepared by contacting 1(2-furyl)-1-ethanol in aqueous solution with two equivalents of a halogen oxidant at room temperature and then heating until the hydrolysis of the formed 4-halo-dihydropyran intermediate is substantially complete. Other valuable related gamma-pyrones are prepared in analogous manner from appropriate alcohols.
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- Derivatives of N-(2,2-dichlorovinyl) salicylamide and use thereof as bactericides, fungicides and algicides for industry
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A new compound represented by the formula STR1 WHEREIN X represents hydrogen atom, chlorine atom, bromine atom, methyl group or nitro group, Y represents hydrogen atom, methyl group, an alkylcarbonyl group where the alkyl group has from 1 to 12 carbon atoms and may be substituted by one or more halogen atoms, a lower alkoxy carbonyl group, a lower alkylamino carbonyl group or a metal atom of which the valence is 1 or 2, Z represents hydrogen atom or chlorine atom and n represents 2 when Y represents a metal atom of which valence is 2 and n represents 1 when Y represents said group or said atom except a metal atom of which valence is 2 but when X and Z represent hydrogen atom, Y does not represent hydrogen atom or a metal atom is employed to control the growth of bacteria, fungi and algae which propagate on industrial raw materials and products or in water in circulating water systems.
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- Optical brightening agents of naphthalimide derivatives
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A naphthalimide derivative having the formula STR1 wherein R is an alkyl, or cycloalkyl, an aralkyl, a haloalkyl, an alkoxyalkyl, a hydroxyalkyl, an N,N-dialkylaminoalkyl, an unsubstituted or halogen-, alkyl-, alkoxy- or hydroxy-substituted aryl, or an ammoniumalkyl; X is a group of the formula, STR2 wherein A is STR3 or an unsubstituted or halogen-substituted arylene, or a group of the formula, STR4 wherein R1 is hydrogen, an alkyl, phenyl, a hydroxyalkyl, or an alkoxyalkyl; Y is --CO--, --COO--, --CONR3 -- (where R3 is hydrogen or an alkyl), or --SO2 --; R2 is hydrogen, an alkyl, a cycloalkyl, an aralkyl, a haloalkyl, an alkyl- or aryl-substituted amino-alkyl, an unsubstituted or halogen-, alkyl-, alkoxy-, hydroxy-, amino- or alkylamino-substituted aryl, a group of the formula, STR5 (where R, R1 and Y are as defined above and R4 is a bivalent group), or a group of the formula, (where R5 is direct linkage or a bivalent group; Q+ is a substituted ammonium, a cycloammonium or a hydrazinium; and α- is an anion), Which is useful for optically brightening an organic polymer material.
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