- Catalyst
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A complex of formula (I): (I′) M is Hf; each X is a sigma ligand; L is a bridge of formula -(ER82)y—; y is 1 or 2; E is C or Si; each R8 is independently a C1-C20-hydrocarbyl, tri(C1-C20-alkyl)silyl, C6-C20- aryl, C7-C20-arylalkyl or C7-C20-alkylaryl or L is an alkylene group such as methylene or ethylene; Ar and Ar′ are each independently an aryl or heteroaryl group optionally substituted by 1 to 3 groups R1 or R1′ respectively; R1 and R1′ are each independently the same or can be different and are a linear or branched C1-C6-alkyl group, C7-20 arylalkyl, C7-20 alkylaryl group or C6-20 aryl group with the proviso that if there are four or more R1 and R1′ groups present in total, one or more of R1 and R1′ is other than tert butyl; R2 and R2′ are the same or are different and are a CH2—R9 group, with R9 being H or linear or branched C1-C6-alkyl group, C3-8 cycloalkyl group, C6-10 aryl group; each R is a —CH2—, —CHRx- or C(Rx)2-group wherein Rx is C1-4 alkyl and where m is 2-6; R5 is a linear or branched C1-C6-alkyl group, C7-20 arylalkyl, C7-20 alkylaryl group or C6-C20-aryl group; R6 is a C(R10)3 group, with R10 being a linear or branched C1-C6 alkyl group; and R6 and R7′ are the same or are different and are H or a linear or branched C1-C6-alkyl group. Invention relates also to a catalyst in solid form comprising (i) a complex of formula (I) and (ii) a cocatalyst of an aluminium compound and (iii) a cocatalyst of a boron compound.
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Paragraph 0426; 0463-0466
(2021/03/16)
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- Preparation method of halogen-substituted alkylaniline
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The invention relates to a preparation method of halogen-substituted alkylaniline, and particularly discloses a method for obtaining halogen-substituted alkylaniline by taking alkylaniline as a raw material to react with hydrobromic acid and hydrogen peroxide in a micro-channel reactor. According to the technical scheme, by adopting the modular micro-channel reaction device, the mass transfer andheat transfer efficiency is improved, and the method has the characteristics of simplicity and safety in operation, high yield and less three wastes, and is suitable for industrial production.
- -
-
Paragraph 0040-0042
(2020/05/02)
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- Asymmetric acyl-Mannich reaction of isoquinolines with α-(diazomethyl)phosphonate and diazoacetate catalyzed by chiral Br?nsted acids
-
An efficient asymmetric acyl-Mannich reaction of isoquinolines with α-(diazomethyl)phosphonate and diazoacetate has been developed using chiral spiro phosphoric acids as catalysts. This reaction allowed the construction of a series of chiral 1,2-dihydroisoquinolines bearing a tertiary stereocenter at the C1 position with up to 98% yield and 99% ee.
- Wu, Wei,Wang, Yan,Guo, Jing,Cai, Liu,Chen, Yuan,Huang, Yanmin,Peng, Yungui
-
supporting information
p. 11235 - 11238
(2020/10/06)
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- Aryl halide and synthesis method and application thereof
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The invention discloses a synthesis method of aryl halides (including aryl bromide shown as a formula (2) and aryl iodide shown as a formula (3)). All the systems are carried out in an air atmosphere,visible light is utilized to excite a substrate or a photosensitizer to catalyze the reaction; and in a reaction solvent, when aromatic hydrocarbon shown in the formula (1) and sodium bromide serve as raw materials, aryl bromide shown in the formula (2) is obtained through a reaction under the auxiliary action of an additive (protonic acid); or when aromatic hydrocarbon shown in the formula (1) and sodium iodide are used as raw materials, under the auxiliary action of an additive (protonic acid), aryl iodide shown in the formula (3) is obtained through reaction. The synthesis method has the advantages of cheap and accessible raw materials, simple reaction operation and mild reaction conditions. The method is compatible with the arylamine which is liable to be oxidized. The invention provides a new method for the synthesis of aryl halides, realizes the amplification of basic chemicals aryl halides including aryl bromide shown in the formula (2) and aryl iodide shown in the formula (3),and has wide application prospect and practical value.
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-
Paragraph 0085-0087
(2020/06/02)
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- Visible-light-promoted oxidative halogenation of (hetero)arenes
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Organic halides are critical building blocks that participate in various cross-coupling reactions. Furthermore, they widely exist as natural products and artificial molecules in drugs with important physiological activities. Although halogenation has been well studied, to the best of our knowledge, studies focussing on sensitive systems (e.g.aryl amines) have not been reported. Herein, we describe a compatible oxidative halogenation of (hetero)arenes with air as the oxidant and halide ions as halide sources under ambient conditions (visible light, air, aqueous system, room temperature, and normal pressure). Moreover, this protocol is practically feasible for gram-scale synthesis, showing potential for industrial application.
- Jiang, Xuefeng,Li, Yiming,Lu, Lingling
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supporting information
p. 5989 - 5994
(2020/10/18)
-
- PROCESS FOR PREPARING PROPYLENE COPOLYMERS COMPRISING C4-C12-ALPHA OLEFIN COMONOMER UNITS
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The present invention relates to a process for producing a copolymer of propylene, optionally ethylene, and at least one comonomer selected from alpha olefins having from 4 to 12 carbon atoms using a specific class of metallocene complexes in combination with a cocatalyst system comprising a boron containing cocatalyst and an aluminoxane cocatalyst, preferably in a multistage polymerization process including a gas phase polymerization step.
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Page/Page column 59
(2020/01/10)
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- CATALYSTS
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A complex of formula (I) wherein M is zirconium or hafnium; each X independently is a sigma ligand; L is a divalent bridge selected from -R'2C-, -R'2C-CR'2-, -R'2Si-, -R'2Si-SiR'2-, -R'2Ge-, wherein each R' is independently a hydrogen atom or a C1-C20-hydrocarbyl group optionally containing one or more silicon atoms or heteroatoms of Group 14-16 of the periodic table or fluorine atoms, and optionally two R' groups taken together can form a ring; R2 and R2' are each independently a C1-C20 hydrocarbyl group, -OC1- hydrocarbyl group or -SC1-20 hydrocarbyl group; R5 is a -OC1-20 hydrocarbyl group or -SC1-20 hydrocarbyl group, said R5 group being optionally substituted by one or more halo groups; R5' is hydrogen or a C1-20 hydrocarbyl group; -OC1-20 hydrocarbyl group or -SC1-20 hydrocarbyl group; said C1-20 hydrocarbyl group being optionally substituted by one or more halo groups; R6 and R6' are each independently a C1-20 hydrocarbyl group; -OC1-20 hydrocarbyl group or -SC1-20 hydrocarbyl group; each R1 and R1' are independently -CH2Rx wherein Rx are each independently H, or a C1-20 hydrocarbyl group, optionally containing heteroatoms.
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Page/Page column 49
(2018/06/06)
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- Novel cyclic bicarbodiimide compound and preparation method of novel cyclic bicarbodiimide compound
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The invention relates to a novel cyclic bicarbodiimide compound (I) and a preparation method of the novel cyclic bicarbodiimide compound. Compared with monocarbodiimide, the novel cyclic bicarbodiimide compound has a higher molecular weight and a higher melting point; the disadvantage that the monocarbodiimide is easily transferred outward from compounds including polyester, polyurethane and like at high temperature is overcome; the anti-hydrolytic property of a material is improved; meanwhile, the defects that an existing bicarbodiimide compound is easily irregularly curled, easily forms a rubber state at room temperature and is not easy to crystallize and purify are overcome; the anti-hydrolytic effect is good and the bicarbodiimide compound has a good anti-hydrolytic property; the service life of a polyester material is improved; the bicarbodiimide compound can be used as an anti-hydrolytic stabilizer and is used for polyurethane and polyester elastomers, and especially can be used for photovoltaic industry, biodegradable materials and the like. The formula (I) is shown in the description.
- -
-
Paragraph 0039
(2017/08/29)
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- Electrophilic aryl-halogenation using N-halosuccinimides under ball-milling
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We report here a methodology of chemo- and regio-selective aryl bromination and iodination using respective N-halosuccinimides at room temperature in the absence of any solvents, catalyst/additives under ball-milling condition. However, for chlorination ceric ammonium nitrate was used as additive. The coupled product succinimide, produced from the reactions, was recycled via regeneration of NBS. This methodology works with the electron-donor substituted or unsubstituted arenes.
- Bose, Anima,Mal, Prasenjit
-
supporting information
p. 2154 - 2156
(2015/03/18)
-
- Efficient and Practical Oxidative Bromination and Iodination of Arenes and Heteroarenes with DMSO and Hydrogen Halide: A Mild Protocol for Late-Stage Functionalization
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An efficient and practical system for inexpensive bromination and iodination of arenes as well as heteroarenes by using readily available dimethyl sulfoxide (DMSO) and HX (X = Br, I) reagents is reported. This mild oxidative system demonstrates a versatile protocol for the synthesis of aryl halides. HX (X = Br, I) are employed as halogenating reagents when combined with DMSO which participates in the present chemistry as a mild and inexpensive oxidant. This oxidative system is amenable to late-stage bromination of natural products. The kilogram-scale experiment (>95% yield) shows great potential for industrial application.
- Song, Song,Sun, Xiang,Li, Xinwei,Yuan, Yizhi,Jiao, Ning
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supporting information
p. 2886 - 2889
(2015/06/30)
-
- Electrophilic aryl-halogenation using N-halosuccinimides under ball-milling
-
We report here a methodology of chemo- and regio-selective aryl bromination and iodination using respective N-halosuccinimides at room temperature in the absence of any solvents, catalyst/additives under ball-milling condition. However, for chlorination ceric ammonium nitrate was used as additive. The coupled product succinimide, produced from the reactions, was recycled via regeneration of NBS. This methodology works with the electron-donor substituted or unsubstituted arenes.
- Bose, Anima,Mal, Prasenjit
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supporting information
p. 2154 - 2156
(2014/04/03)
-
- Metal-free C-N bond-forming reaction: Straightforward synthesis of anilines, through cleavage of aryl C-O bond and amide C-N bond
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An efficient metal-free C-N bond forming reaction through cleavage of aryl C-O bond and amide C-N bond has been developed. This process represents a practical method for the facile construction of anilines with a broad substrate scope and wide functional group tolerance in moderate to excellent yields.
- Yu, Jianzhong,Zhang, Peizhi,Wu, Jun,Shang, Zhicai
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supporting information
p. 3167 - 3170
(2013/06/27)
-
- Mechanistic insight into the formal [1,3]-migration in the thermal claisen rearrangement
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The thermal formal [1,3]-sigmatropic shift of allyl aryl ethers has been studied in depth experimentally with the aid of the density functional theory (DFT) calculations of the B3LYP function. Three mechanistic possibilities, referred to as the radical, ionic, and concerted mechanisms, have previously been put forth to explain the thermal [1,3]-rearrangement process. However, the intercrossing and radical trapping experiments indicate the rearrangement is an intramolecular process. The computational studies reveal that the concerted C[1,3]-sigmatropic shift suffered from a higher energetic barrier to allow the rearrangement to proceed under the conditions used. However, a tandem O[1,3]-sigmatropic shift with a configuration inversion of the oxygen atom and [3,3]-sigmatropic shift (the Claisen rearrangement) is the most likely pathway for the formal [1,3] rearrangement. Furthermore, the rearrangement experiments with a designed optically active substrate and O[1,3]-sigmatropic shift examples verify the new cascade rearrangement. In addition, computational and experimental studies indicate that water molecule assists the proton shift during the isomerization. The combined methods provide the new insight into the mechanism of the thermal formal [1,3]-migration in the Claisen rearrangement and the novel O[1,3]-sigmatropic shift as well.
- Hou, Shili,Li, Xinyao,Xu, Jiaxi
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p. 10856 - 10869
(2013/02/23)
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- N-Heterocyclic carbene containing element organic frameworks as heterogeneous organocatalysts
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A bifunctional imidazolium linker was used for the production of highly crosslinked element organic frameworks by Suzuki-coupling with tetrafunctional boronic acids. The resulting porous materials are good heterogeneous organocatalysts in the N-heterocyclic carbene-catalyzed conjugated umpolung of α,β-unsaturated cinnamaldehyde. The Royal Society of Chemistry 2011.
- Rose, Marcus,Notzon, Andreas,Heitbaum, Maja,Nickerl, Georg,Paasch, Silvia,Brunner, Eike,Glorius, Frank,Kaskel, Stefan
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supporting information; scheme or table
p. 4814 - 4816
(2011/06/22)
-
- Mild, efficient, and regioselective monobromination of arylamines and phenols using [BBIm]Br3 as a new reagent
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We report here an efficient method for the synthesis and characterization of the room-temperature ionic liquid 1,3-di-n-butylimidazolium tribromide ([BBIm]Br3) (2) and its application as an efficient reagent and solvent for regioselective bromination of arylamines and phenols under mild conditions. The bromination was carried out in the absence of organic solvents, and in most cases, the only extraction solvent needed was water. The spent 1,3-di-n-butylimidazolium bromide (1) was easily recycled.
- Borikar, Sanjay P.,Daniel, Thomas,Paul, Vincent
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experimental part
p. 647 - 653
(2011/02/27)
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- An efficient, rapid, and regioselective bromination of anilines and phenols with 1-butyl-3-methylpyridinium tribromide as a new reagent/solvent under mild conditions
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1-Butyl-3-methylpyridinium tribromide, [BMPy]Br3 proves to be a highly efficient, regioselective reagent/solvent for nuclear bromination of various anilines and phenols. The synthesis and characterization of the room temperature ionic liquid [BMPy]Br3 (2) is described. The bromination was carried out in the absence of organic solvents and in most cases the only extraction solvent needed was water. The spent 1-butyl-3-methylpyridinium bromide (1) was easily recycled.
- Borikar, Sanjay P.,Daniel, Thomas,Paul, Vincent
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scheme or table
p. 1007 - 1009
(2009/05/11)
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- Regioselective bromination of aromatic amines and phenols using N-benzyl-DABCO tribromide
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N-Benzyl-DABCO tribromide, a stable, solid organic ammonium tribromide, has been used as a bromine source for the regioselective and high-yielding bromination of aromatic amines and phenols. Mono-bromination proceeds well in the presence of a stoichiometric amount of bromine source at room temperature.
- Moghaddam, Firouz Matloubi,Zargarani, Dordaneh
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experimental part
p. 4212 - 4220
(2010/01/08)
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- HALOGEN SUBSTITUTED METALLOCENE COMPOUNDS FOR OLEFIN POLYMERIZATION
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A metallocene compound is represented by the formula (1): AMXn-1 wherein M is a transition metal atom having a coordination number of n selected from Group 3, 4, 5 or 6 of the Periodic Table of Elements, or a lanthanide metal atom, or actinide metal atom; A is a substituted monocyclic or polycyclic arenyl ligand pi-bonded to M, wherein said arenyl ligand includes at least one halogen substituent directly bonded to any sp2 carbon atom at a bondable ring position of the ligand; and the or each X is a univalent anionic ligand, or two X are joined and bound to the metal atom to form a metallocycle ring, or two X are joined to form a chelating ligand, a diene ligand, or an alkylidene ligand.
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Page/Page column 119
(2010/11/27)
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- Halogen substituted metallocene compounds for olefin polymerization
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A metallocene compound is represented by the formula (1): [in-line-formulae]AMXn-1 [/in-line-formulae]wherein M is a transition metal atom having a coordination number of n selected from Group 3, 4, 5 or 6 of the Periodic Table of Elements, or a lanthanide metal atom, or actinide metal atom; A is a substituted monocyclic or polycyclic arenyl ligand pi-bonded to M, wherein said arenyl ligand includes at least one halogen substituent directly bonded to any sp2 carbon atom at a bondable ring position of the ligand; and the or each X is a univalent anionic ligand, or two X are joined and bound to the metal atom to form a metallocycle ring, or two X are joined to form a chelating ligand, a diene ligand, or an alkylidene ligand.
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-
- Tetrameric DABCO-bromine: An efficient and versatile reagent for bromination of various organic compounds
-
Tetrameric DABCO-bromine is a powerful brominating agent but shows reasonable selectivity with certain substrates. The selective bromination for activated aromatic compounds and alkenes is reported. Synthesis of α-bromo ketones and nitriles has also been achieved by using this reagent and the results are also reported. All products reported were obtained in good to excellent yields.
- Heravi, Majid M.,Derikvand, Fatemeh,Ghassemzadeh, Mitra
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p. 125 - 128
(2007/10/03)
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- Regioselective and high-yielding bromination of aromatic compounds using hexamethylenetetramine-bromine
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A regioselective and highly efficient method for bromination of aromatic compounds in the presence of a stoichiometric amount of hexamethylenetetramine- bromine (HMTAB) as an efficient reagent in dichloromethane is reported. The selectivity depends on the temperature and nature of the substituent on the substrate. The reactivity of this reagent was increased by supporting it to silica gel for bromination of less activated compounds.
- Heravi, Majid M.,Abdolhosseini, Nafiseh,Oskooie, Hossein A.
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p. 8959 - 8963
(2007/10/03)
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- Transformation of mutagenic aromatic amines into non-mutagenic species by alkyl substituents: Part I. Alkylation ortho to the amino function
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Alkyl-substituted derivatives of 2-aminonaphthalene (2-AN) 1, 2-aminofluorene (2-AF) 6 and 4-aminobiphenyl (4-ABP) 11 were synthesized and the mutagenic activity of these compounds determined in Salmonella typhimurium strains TA98 and TA100 with and without S9 mix. In the case of the ortho-substituted 4-aminobiphenyls 12-15 (3-alkyl = ethyl, iso-propyl, n-butyl, tert-butyl) the substituent with the strongest steric demand (3-tert-butyl) shows the strongest influence on the decrease of mutagenicity if compared with the parent compound. In the series of the bis-ortho-disubstituted compounds 16-18 (3,5-dimethyl-, 3,5-diethyl- and 3,5-diisopropyl-4-aminobiphenyl) generation of non-mutagenic species occurs already with the introduction of two ethyl groups. For the 4-aminobiphenyl derivatives 12-15 and 16-18, as well as for the 1-alkylated 2-aminofluorenes 7-10 and the 1-alkylated 2-aminonaphthalenes 2-5 a smaller mutagenicity was observed if compared with predicted mutagenicities as calculated by the QSAR equations of Debnath et al. (Environ. Mol. Mutagen. 19 (1992) 37). The largest differences resulted in the cases of the tert-butyl substituted compounds. Only with smaller alkyl groups like ethyl the QSAR predictions and the experimentally determined mutagenicities come close to each other. Thus, these results show that appropriate alkyl substitution reduces (eliminates) mutagenicity, secondly, it is necessary to introduce steric parameters to predict the mutagenicity of such compounds correctly.
- Glende, Carsten,Schmitt, Heimo,Erdinger, Lothar,Engelhardt, Guenter,Boche, Gernot
-
-
- Halide ion trapping of nitrenium ions formed in the Bamberger rearrangement of N-arylhydroxylamines. Lifetime of the parent phenylnitrenium ion in water
-
The data of p-aminophenol, the product of Bamberger rearrangement, Were analyzed by a mechanism involving rate-limiting formation of the appropriate arylnitrenium ion followed by product-determining steps in involving trapping by the solvent or by the added halide. The possibility that a portion of the halide-trapped products were derived from a pre-association mechanism was also include. Kinetic analyses then produced kBr:kw and kCl:kw ratios for two limiting cases, one involving pre-association with an equilibrium constant Kas = 0.3, and one ignoring pre-association. From an azide:water ratio (kAz:kw) previously determined for the 2,6-dimethylphenylnitrenium, kBr was concluded to lie in the range (4-5) × 109 M-1 s-1 for all of the nitrenium ions of this study. This range for kBr then led to kw values of (1-2) × 109 s-1 (2,5-Me2), (2-3) × 109 s-1 (2-Me), and (4-8) × 109 s-1 (parent and 2-Cl), where the ranges reflect uncertainties in the exact value of kBr and in the contribution from pre-association. The lifetime of the parent phenylnitrenium ion in water at one molar ionic strength is concluded to lie in the range 125-250 ps.
- Fishbein,McClelland
-
p. 1321 - 1328
(2007/10/03)
-
- Efficient asymmetric hydrogenation of (Z)-2-acetamidocinnamic acid catalyzed by the rhodium complex of modified n-Benzyl-(3R,4R)-3,4-bis(diphenylphosphino)pyrrolidine (degphos)
-
Modified Degphoses (R,R)-MOD-, XYL-Degphos) have been prepared and catalytic asymmetric hydrogenetion of (Z)-2-acetamidocinnamic acid was carried out with their rhodium(]) cationic complexes. The catalytic activities of the modified Degphoses were enhanced.
- Inoguchi,Achiwa
-
p. 818 - 820
(2007/10/02)
-
- 3-amino-5-methyl-1H-pyrazole-4-carboxylic acids and esters thereof as anticonvulsants, muscle relaxants and anxiolytics
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A novel method of controlling epilepsy, muscle tension, muscular spasticity, and anxiety in living animal bodies by administering compounds of the formula: STR1 wherein: R1 is hydrogen, loweralkyl or a pharmaceutically acceptable cation; R2 and R3, same or different, are hydrogen, loweralkyl, aryl, cycloalkyl, loweralkenyl, 1-adamantyl, heterocyclicaminoalkyl, diloweralkylaminoloweralkyl, or R2 with R3 and adjacent nitrogen may form a heterocyclic ring structure; and the pharmaceutical acceptable acid salts, and tautomeric isomers thereof; and novel pharmaceutical compositions therefor are disclosed.
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-
- Revisitation of Formaldehyde Aniline Condensation. VIII. - Monomeric N-Methylene Anilines
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A convenient, high yield "dry" method of synthesis of monomeric N-methyleneanilines (6a-i) and the characterization of the products by m.s., 1H- and 13C-n.m.r. and i.r. are reported, improving previous procedures and describing new compounds.It appeared that the existence of monomeric N-methyleneanilines is stricly related to the presence of enough steric hindrance to oligomerization by substituents in ortho positions.Moreover, some addition products of formaldehyde to an amine and its corresponding imines are tentatively identified on the basis of the observed mass spectrum of the whole reaction mixture.The reaction products of formaldehyde with 2,6-dimethylaniline (1a) provided an example of a mobile equilibrium between monomeric and trimeric imine.
- Giumanini, Angelo G.,Verardo, Giancarlo,Polana, Marco
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p. 161 - 174
(2007/10/02)
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- Halogenation Using Quaternary Ammonium Polyhalides. VI. Bromination of Aromatic Amines by Use of Benzyltrimethylammonium Tribromide
-
The reaction of aromatic amines with benzyltrimethylammonium tribromide in dichloromethane-methanol containing calcium carbonate powder for 0.5 h at room temperature gave bromo-substituted aromatic amines in good yields.
- Kajigaeshi, Shoji,Kakinami, Takaaki,Inoue, Kazuhisa,Kondo, Manabu,Nakamura, Hiroko,et al.
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p. 597 - 599
(2007/10/02)
-
- Vinyl Cation Intermediates in Solvolytic and Electrophilic Reactions. 1. Solvolysis of α-Arylvinyl Derivatives
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The solvolysis of 16 α-arylvinyl tosylates, bromides, and chlorides has been investigated in various alcohol-water mixtures and in acetic acid at several temperatures.All substrates were substituted with either 2-methyl or 2,6-dimethyl groups to accelerate the rates of reaction.The major or exclusive product isolated in most cases was the acetophenone arising from hydrolysis of the expected enol ethers or acetates during workup.The kinetics were simple first order in the vast majority of cases, with excess base added to prevent side reactions.Leaving group effects, Winstein-Grunwald m values, Schleyer Q values, and effects of solvent nucleophilicity all point to a limiting SN1 ionization generating a vinyl cation intermediate, in which there is little rear-side nucleophilic assistance by solvent.Substituent effects led to ρ values in the range -3.9 to -5.3 vs. ?+.Activation parameters are typical for an SN1 process, and ΔS% is insensitive to the presence of zero, one, or two o-methyl groups, as are the effects of solvent polarity on the rates.The results should therefore be directly comparable with other solvolytic or electrophilic reactions generating formally similar vinyl cation intermediates.
- Yates, Keith,Mandrapilias, George
-
p. 3892 - 3902
(2007/10/02)
-