- POLYMERIZATION CATALYSTS
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Embodiments of the present disclosure directed towards polymerization catalysts having improved ethylene enchainment and/or improved catalyst productivity. As an example, the present disclosure provides a polymerization catalyst of Formula (I), wherein each of R1 to R12 is independently a C1 to C20 alkyl, aryl or aralkyl group, or a hydrogen, wherein at least one of R4 to R7 is not a hydrogen, wherein M is a Group 4 metal, and wherein, each X is independently a halide, C1 to C20 alkyl, aralkyl or hydrogen
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Paragraph 0128-0130
(2019/09/06)
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- CATALYST COMPRISING A METALLOCENE COMPLEX AND A CO-CATALYST
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The invention relates to a metallocene complex (1) according to formula (I) wherein M is a metal selected from lanthanides or transition metals from group 3, 4, 5 or 6 of the Periodic System of the Elements, Q is an anionic ligand to M, k is the number of Q groups and equals the valence of M minus 2, R is a bridging group containing at least one carbon atom bonded to the indenyl moiety at 2-position, R1, R2, R3 and R4 are each independently chosen from the group consisting of H, a halogen atom and a C1-C20 hydrocarbylgroup, and wherein at least one of R1 and R2 is not H, and at least one of R3 and R4 is not H. The invention also relates to a catalyst comprising the metallocene complex, to a process for making polyolefins and to the use of the polyolefins for making articles.
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Page/Page column 15
(2016/12/16)
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- Ruthenium Trichloride Catalyzed Highly Efficient Deoximation of Oximes to the Carbonyl Compounds and Nitriles without Acceptors
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An acceptor-free catalysis protocol for the deoximation of ketoximes and aldoximes using RuCl3 as the catalyst has been developed. Under the optimized conditions, various oximes were converted to ketones and nitriles with excellent isolated yields. An acceptor-free catalysis protocol for the deoximation of ketoximes and aldoximes using RuCl3 as the catalyst has been developed. Under the optimized conditions, various oximes were converted to ketones and nitriles with excellent isolated yields.
- Liu, Yuxiao,Yang, Na,Chu, Changhu,Liu, Renhua
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supporting information
p. 1011 - 1014
(2015/09/28)
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- Tuning the rotation rate of light-driven molecular motors
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Overcrowded alkenes are among the most promising artificial molecular motors because of their ability to undergo repetitive light-driven unidirectional rotary motion around the central C=C bond. The exceptional features of these molecules render them highly useful for a number of applications in nanotechnology. Many of these applications, however, would benefit from higher rotation rates. To this end, a new molecular motor was designed, and the isomerization processes were studied in detail. The new motor comprises a fluorene lower half and a five-membered-ring upper half; the upper-half ring is fused to a p-xylyl moiety and bears a tert-butyl group at the stereogenic center. The kinetics of the thermal isomerization was studied by low-temperature UV-vis spectroscopy as well as by transient absorption spectroscopy at room temperature. These studies revealed that the tert-butyl and p-xylyl groups in the five-membered-ring upper half may be introduced simultaneously in the molecular design to achieve an acceleration of the rotation rate of the molecular motor that is larger than the acceleration obtained by using either one of the two groups individually. Furthermore, the new molecular motor retains unidirectional rotation while showing remarkably high photostationary states.
- Bauer, Jurica,Hou, Lili,Kistemaker, Jos C. M.,Feringa, Ben L.
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p. 4446 - 4455
(2014/06/09)
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- Synthesis of 7-substituted derivatives of 5, 8-dimethylisoquinoline
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7-Bromo-5,8-dimethylisoquinoline was selectively synthesized by the bromination of 5,8-dimethylisoquinoline obtained in five steps from p-xylene as a starting material. Further,7-bromo-5,8-dimethylisoquinolinegave 7-amino-5,8-dimethylisoquinoline by the reaction with ammonia and various 7-anilino-5,8-dimethylisoquinolines via a palladium-catalyzed coupling reaction with anilines.
- Nagao, Yukinori,Hirota, Katsuaki,Tokumaru, Mizuho,Kozawa, Kozo
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body text
p. 593 - 602
(2009/09/28)
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- 4-(2-Methyl-5,6,7,8-tetrahydro-quinolin-7-ylmethyl)-1,3-dihydro-imidazole-2-thione as specific alpha2B agonist and methods of using the same
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The compound of the formula wherein the * indicates an asymmetric carbon, is specific to alpha2B adrenergic receptors in preference over alpha2A and alpha2C adrenergic receptors, and as such has no or only minimal cardivascular and/or sedatory activity. The compound is useful as medicament in mammals, including humans, for treatment of diseases and or alleviations of conditions which are responsive to treatment by agonists of alpha2B adrenergic receptors.
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- 4-SUBSTITUTED IMIDAZOLE-2-THIONES AND IMIDAZOL- 2-ONES AS AGONISTS OF THE ALPHA- 2B AND ALPHA-2C ADRENERGIC RECEPTORS
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Compounds of Formula (I): where X is S and the variables have the meaning defined in the specification are specific or selective to alpha2B and/or alpha2C adrenergic receptors in preference over alpha2A adrenergic receptors, and as such have no or only minimal cardivascular and/or sedatory activity. These compounds of Formula (I) are useful as medicaments in mammals, including humans, for treatment of diseases and or alleviations of conditions which are responsive to treatment by agonists of alpha2B adrenergic receptors. Compounds of Formula (I) where X is O also have the advantageous property that they have no or only minimal cardivascular and/or sedatory activity and are useful for treating pain and other conditions with no or only minimal cardivascular and/or sedatory activity.
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- Electron-transfer-induced tautomerization in methylindanones: Electronic control of the tunneling rate for enolization
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The radical cations generated from 4-methyl- and 4,7-dimethylindanone, as well as their deuterated isotopomers, isolated in Argon matrices, were found to undergo enolization to the corresponding enol radical cations at rates that differ by orders of magnitude. It is shown by quantum chemical calculations that the effect of the remote methyl group in the 4-position is of purely electronic nature in that it stabilizes the unreactive π-radical relative to the reactive σ-radical state of the 7-methylindanone radical cation. The observed kinetic behavior of the two compounds can be reproduced satisfactorily on the basis of calculated heigth and width of the thermal barrier for enolization, using the Bell model for quantum mechanical tunneling. High-level calculations on the methylacrolein radical cation show that barriers for enolization in radical cations are overestimated by B3LYP/6-31G*.
- Bednarek,Zhu,Bally,Filipiak,Marcinek,Gebicki
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p. 2377 - 2387
(2007/10/03)
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- Bridged metallocene complex for the (co) polymerization of olefins
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A “bridged” bis-cyclopentadienyl complex which can be advantageously used for the formation of a catalytic system active in the (co)polymerization of ethylene and other a-olefins is represented by means of the following formula (II): wherein: M represents a metal selected from titanium, zirconium or hafnium; A′ and A″ each independently represent an anion containing an η5-cyclopentadienyl ring coordinated to M; or R″ each independently represents a group of an anionic nature a-bound to the metal M; B represents an unsaturated bivalent organic residue having from 1 to 30 carbon atoms bound, respectively, to the ring of group and to the -CH2- methylene group by means unsaturated carbon atoms. This complex, combined with a suitable cocata forms a catalyst with a high activity in the poization of olefins, producing polymers with molecular weight, especially in the case of the merization of ethylene with a second α-olefir.
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- Synthesis of substituted indeno[1,2-b]quinoline-6-carboxamides, [1]benzothieno[3,2-b]quinoline-4-carboxamides and 10H-quindoline-4-carboxamides: Evaluation of structure-activity relationships for cytotoxicity
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New substituted indeno[1,2-b]quinoline-6-carboxamides, [1]benzothieno[3,2-b]quinoline-4-carboxamides and 10H-quindoline-4-carboxamides were prepared from methyl 2-amino-3-formylbenzoate by a new Friedlander synthesis. Evaluation of these carboxamides for cytotoxicity in a panel of cell lines showed that small lipophilic substituents in the non-carboxamide ring, in a pseudo-peri position to the side chain, significantly increased cytotoxic potency while retaining a pattern of cytotoxicity consistent with a non-topo II mode of action. The methyl-substituted indeno[1,2-b]quinoline-6-carboxamide demonstrated substantial effectiveness (20-day growth delays) in a sub-cutaneous colon 38 in vivo tumor model. This is comparable to that reported for the dual topo I/II inhibitor DACA that is in clinical trial. Copyright (C) 2000 Elsevier Science Ltd.
- Chen, Junjie,Deady, Leslie W.,Desneves, Jose,Kaye, Anthony J.,Finlay, Graeme J.,Baguley, Bruce C.,Denny, William A.
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p. 2461 - 2466
(2007/10/03)
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- Synthesis and Na+/H+ exchange inhibitory activity of indanylideneacetylguanidines
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Synthesis of indanylideneacetylguadines 7a-i and their corresponding reduced compounds 8a-e has been achieved and their Na+/H+ exchange inhibitory activity evaluated. All the compounds studied exhibit significant inhibition of Na+/H+ exchanger activity. Promising activity is shown by compounds 7g, 8b and 8d. From the structure activity analysis, it appears that reduction of exocyclic double bond is associated with a marked increase in inhibitory activity.
- Ramakrishna,Jain,Ghate,Gupte,Vadlamudi
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p. 407 - 412
(2007/10/03)
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- Process for the preparation of amorphous polymers of propylene
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It is possible to prepare substantially amorphous polymers of propylene endowed with high molecular weights, operating at temperatures of industrial interest, by carrying out the polymerization reaction of propylene in the presence of metallocene catalysts comprising particular bis-indenyl or bis-4,5,6,7-tetrahydroindenyl compounds substituted in the 2-position on the indenyl or tetrahydroindenyl groups.
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- Aromatic Spiranes XX [1]: Syntheses of Dimethylsubstituted 2-Carboxymethyl-indan-1-ones and Benzylchlorides as Synthones for Syntheses of di- to tetramethylsubstituted Spirobiindandiones
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The isomeric dimethyl methylbenzoates 5, obtained from the bromides via Grignard reactions with dimethylcarbonate, were reduced with LiAlH4 to the hydroxymethyl derivatives 6. The latter were then transformed both to the benzylchlorides 7 (with SOCl2) and to the aldehydes 8 (with pyridinium chlorochromate). Knoevenagel-Doebner reaction of 8 afforded the acrylic acids 9 which (after hydrogenation to 11) were cyclized to the desired indanones 12 with polyphosphoric acid. On the other hand, 12c and 12e were prepared from dimethyl 3-chloropropiophenone (14) by warming with sulfuric acid. After NaH-catalyzed reaction with dimethylcarbonate, the indanones 12 gave the ketoesters 15 which then could be hydrogenated to the indanes 16. All reactions proceeded with satisfactory to excellent yields (60-90%).
- Neudeck
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p. 185 - 200
(2007/10/03)
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- SCHWEFELVERBINDUNGEN DES ERDOELS XXII. ALKYL-10,11-DIHYDRODIINDENOTHIOPHENE
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The one-pot syntheses of alkyl-10,11-dihydrodiindenothiophenes (3) by bromination and sulfurization of alkylindan-1-ones without substituents at C-2 (1) has been studied with 14 1 with C1-C4-rests at the benzene and or the cyclopentane ring. 9 dialkyl-3 and 3 tetraalkyl-3 are prepared in yields of 7-66percent; an octamethyl-3 is detected by tlc and ms. 2 dialkyl-3 are prepared too by an independent syntheses from dimethyl 2,5-bis(methylphenyl)thiophene-3,4-dicarboxylates (13).The mechanism of the one-pot syntheses, which gives diindeno-1,4-dithiines too,is discussed.The oxidation of 4 3 has been studied.Key words: Alkylindan-1-ones, alkyl-10,11-dihydrodiindenothiophenes, alkyldiindeno-1,4-dithiines, one-pot syntheses of anellated thiophenes, oxidation of anellated thiophenes.
- Boberg, Friedrich,Deters, Karin,Schulz, Juergen,Torges, Karl-Franz
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- Electron Paramagnetic Resonance Spectra of the Radical Cations of Some Benzocyclobutenes, Benzocyclopentenes and Benzocyclohexenes
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1,2,4,5-Tetrahydrobenzodicyclobutene, 1,2,3,5,6,7-hexahydrobenzodicyclopentene and 1,2,3,4,6,7,8,9-octahydrobenzodicyclohexene, and their dimethyl derivatives, and tetramethylbenzocyclo-butene, -pentene and -hexene have been prepared.All except the first compound have been oxidised to their corresponding radical cations, and the EPR spectra have been analysed by assigning McConnell-type Q-values to the substituents in the benzene ring.It is suggested that the ordering of the orbital energy levels (ΨA above ΨS) in 3,6-dimethylbenzobiscyclobutene and -pentene is a manifestation of the Mills-Nixon effect, and results from rehybridisation of the strained molecular framework.In the radical cations of 5,10-dimethyl-1,2,3,4,6,7,8,9-octahydrobenzodicyclohexene and 5,6,7,8-tetramethyl-1,2,3,4-tetrahydrobenzocyclohexene the total unpaired electron density, as implied by the McConnell type of relationship, appears to be less than unity.Various possible causes of this are examined.
- Avila, David V.,Davies, Alwyn G.,Li, Elizabeth R.,Ng, Kai M.
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p. 355 - 362
(2007/10/02)
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- Compounds and compositions
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The invention concerns novel compounds of the formula I STR1 wherein: W are selected from alkyl, alkenyl and alkynyl; X are selected from halogen, nitro, cyano, alkyl, substituted alkyl, hydroxy, alkoxy, substituted alkoxy, alkenyl, alkynyl, alkenyloxy, alkynyloxy, acyloxy, alkoxycarbonyl, alkylthio, alkylsulfinyl, alkylsulfonyl, sulfamoyl, substituted sulfamoyl, amino, substituted amino, and the groups formyl and alkanoyl and the oxime and imine derivatives thereof, and an alkylene group which bridges two adjacent carbon atoms of the benzene ring; R1 is selected from hydrogen, alkyl, alkenyl, alkynyl, substituted alkyl, alkylsulfonyl, arylsulfonyl, acyl and an inorganic or organic cation; R2 is selected from alkyl, substituted alkyl, alkenyl, haloalkenyl, alkynyl and haloalkynyl; R3 is selected from alkyl, fluoroalkyl, alkenyl, alkynyl, and phenyl; p is zero or an integer selected form 1 to 4; n is zero or an integer selected from 1 to 3; and m is zero or an integer selected from 1 to 3. The compounds of the invention show cereal selective herbicidal properties and plant growth regulating properties and in further embodiments the invention provides processes for the preparation of the compounds of formula I, intermediates useful in the preparation of the compounds of formula I, compositions containing as active ingredient a compound of formula I, and herbicidal and plant growth regulating processes utilizing compounds of formula I.
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- Cyclophane, XXVII. - Indenophane Mono- and Dianions: Preparation and Nuclear Magnetic Resonance Spectra
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The preparation and chemical and physical properties of negatively charged polycyclic cyclophanes are reported.The through-space electronic interactions and the through-space anisotropy effects were deduced from proton and carbon nuclear magnetic resonance data.The systems studied belong to two main groups: a) 4n ?-polycyclic dianions which are paratropic, e.g. benzochrysenophane dianion (122-), and b) (4n + 2)?-polycyclic mono- and dianions, which are diatropic.In the dianions both layers are charged, e.g. syn-indenocyclophane (132-) and its anti iomer (142-).The monoanions studied are benzoindenocyclophane (151-), 4,5,17,18-tetramethylbenzoindenocyclophane(161-), and 12-methylbenzoindenocyclophane (171-).The spectroscopic properties of the layered anions were compared with those of 1,4-dimethylindenyl anion (111-) and with the literature data of the neutral cyclophanes, viz. 1-11.A differentiation between the anisotropy and charge-transfer effects has been made and it enables the estimation of the net through-space interaction. - Keywords: Cyclophane anions/ Indene derivatives
- Frim, Ron,Rabinovitz, Mordecai,Bodwell, Graham,Raulfs, Friedrich-Wilhelm,Hopf, Henning
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p. 737 - 744
(2007/10/02)
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- Modern Friedel-Crafts chemistry XIII. Intra- and intermolecular cyclization of some carbonyl derivatives under Friedel-Crafts conditions
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Carbonyl group deactivation in the cycloalkylation of aryl haloalkyl ketones was studied.Ketones 1-5 were prepared and subjected to treatment with AlCl3, AlCl3/H2SO4 and H2SO4 catalysts.Whereas AlCl3 catalyst gave no cyclization products, the use of AlCl3/H2SO4 and H2SO4 catalysts afforded the corresponding indanones and/or tetralones (6-11).The intermediate p-methylacrylophenone (12) was also obtained in the case of ketone 2.Furthermore intermolecular cyclizations of benzene, toluene and p-xylene with 3-chloropropionyl chloride (13) and 4-chlorobutyryl chloride (14) were investigated.In the presence of AlCl3/CH3NO2 catalyst, only the corresponding aryl haloalkyl ketones (1-5) were formed whereas the use of AlCl3 catalyst gave, in addition, some cyclic ketones.However, the use of AlCl3/H2SO4 catalyst gave only the corresponding cyclic ketones (6-11).Results are discussed and mechanisms are suggested.In conclusion, carbonyl group deactivation for ring closure is demonstrated in the investigated ketones and cyclization can only effected under strenuous conditions.
- Khalaf, Ali A.,Abdel-Wahab, Aboel-Magd A.,El-Khawaga, Ahmed M.,El-Zohry, Maher F.
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p. 285 - 291
(2007/10/02)
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- Stereopopulation Control. 8. Rate and Equilibrium Enhancement in the Formation of Homophthalic Anhydrides
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The kinetics of cyclization of α,α,3,4,6-pentamethylhomophthalic acid have been measured in sovent acetonitrile at 28.5 deg C, using as catalysts a series of acids ranging in strength from perchloric to acetic.In the presence of 0.12 M HClO4, t1/2 for acid anhydride formation = 0.3 s.For the stronger acid catalysts, kcycl is a linear function of catalyst concentration; for the weak acids, however, a change in rate-limiting step is revealed by curvature in the plots of ktotobsd vs. .All the weak acids show the same limiting value, 6.45E-3 min-1; this value is considered to be the rate constant for uncatalyzed formation of the tetrahedral intermediate.Homoconjugate bases (HA2(-)) of the weak acids show a similar curvature in their dilution plots, and the same limiting rate constant as for weak acids.Two independent and competitive pathways for cyclization are proposed.For strong acid catalysis, an intermediate acylium ion is considered on the basis of Broensted α = -0.79, kH/kD ca. 1, and acceleration of anhydride hydrolysis by methyl substituents.A value of ΔSexcit. = -23 eu suggests that cyclization, rather than acylium ion formation, is rate limiting.For weak acid catalysis, α = -0.17, kH/kD = 4.3, ΔSexcit. = -31 eu, and methyl groups retard anhydride hydrolysis by electron release; for this pathway, catalyzed breakdown of a tetrahedral intermediate is considered rate limiting.The composite Broensted plot is curved because the two pathways follow different rate laws.In contrast to rate enhancement results for phenolic lactone formation, the pentamethylhomophthalic acid is only sevenfold as reactive as α,α-dimethylhomophthalic acid.For the catalyst acids, pK(acetonitrile) is shown to be a linear function of pK(H2O) over the entire range of acids examined.
- Hillery, Paul S.,Cohen, Louis A.
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p. 2760 - 2770
(2007/10/02)
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