- Conformational stability from variable temperature FT-IR spectra of xenon solutions and ab initio calculations of trans 3-pentenenitrile and 3-methyl-3-butene nitrile
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The infrared (3500-40 cm-1) spectra of gaseous, liquid and solid 3-methyl-3-butene nitrile, CH2C(CH3)CH2CN, and trans 3-pentenenitrile, CH3CHCHCH2CN, have been recorded. Both the cis and ga
- Guirgis,Shen,Drew,Durig
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Read Online
- Nickel-catalyzed isomerization of 2-methyl-3-butenenitrile to 3-pentenenitrile: A kinetic study using in situ FTIR-ATR spectroscopy
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The isomerization of 2-methyl-3-butenenitrile (2M3BN) to 3-pentenenitrile (3PN) was followed using operando FTIR spectroscopy. The spectra were analyzed comprehensively to obtain kinetic profiles from the different band dynamics. Several spectral regions were transformed to their second derivative in order to improve the peak resolution. The dynamics in the spectra were calculated and normalized to the end conversion towards 3PN determined by GC. Similar kinetic profiles were obtained from the dynamics of different bands. Furthermore, calculations on the DFT level were performed for 2M3BN and trans- and cis-3PN in order to help identifying the corresponding bands in the spectra of the reaction mixture. An average conversion profile was calculated from different bands of the substrate and the product, applying a "quasi-multivariate analysis" technique to correlate different band dynamics. This approach was validated using advanced chemometrics. These profiles obtained by IR spectroscopic analysis for the formation of 3PN and the consumption of 2M3BN showed a zero order kinetic.
- Bini, Laura,Houben, Erwin J.E.,Pidko, Evgeny A.,Müller, Christian,Vogt, Dieter
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- Rational design of efficient steric catalyst for isomerization of 2-methyl-3-butenenitrile
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The catalytic isomerization of 2-methyl-3-butenenitrile (2M3BN), a model reaction in the DuPont process, has been performed using NiL4 (L=tri-O-p-tolyl phosphite) as a catalyst. The lowered catalytic activity in the isomerization with coexistence of 2-pentenenitrile (2PN) and 2-methyl-2-butenenitrile (2M2BN) indicates that both 2PN and 2M2BN are the catalyst inhibitors, and the quantitative relationship between the conversion of 2M3BN and the content of 2M2BN and 2PN is provided. DFT calculation results suggest that the inhibition effect is attributed to the generation of dead-end intermediates (2PN)NiL2 and (2M2BN)NiL2, both of which take nickel atom out of the catalytic cycle in the isomerization process. To suppress the inhibition effect, new catalytic intermediates are rationally designed based on their computational %Vbur. An efficient method that adding extra ligand 1, 5-bis(diphenylphosphino)pentane (dppp5) to the NiL4 catalyst is selected experimentally. Compared to the results obtained with NiL4 as catalyst, the (dppp5)NiL2 increases the conversion of 2M3BN from 74.5 % to 93.4 % at 3 h of reaction and provides a high selectivity to 3PN (> 98 %) at optimal conditions.
- Han, Minghan,Liu, Kaikai,Wang, Tiefeng
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Read Online
- Raman and infrared spectra, conformational stability, normal coordinate analysis, vibrational assignment, and ab initio calculations of trans-3-pentenenitrile
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The Raman (3200-20 cm-1) spectra of liquid and solid trans-CH3CH=CHCH2CN, and the infrared (3200-30 cm-1) spectra of gaseous and solid trans-3-pentenenitrile have been recorded. The spectra of the fluid phases are consistent with two stable conformers in equilibrium at ambient temperature. The mid-infrared spectra of the sample dissolved in liquid xenon as a function of temperature (-100 to -55°C) have been recorded. Utilizing two conformer pairs, the enthalpy difference has been determined to be 205 ± 7 cm-1 (2.45 ± 0.08 kJ/mol) with the syn conformer being the more stable form. Vibrational assignments for the 33 normal modes for the syn conformer and several of those for the gauche form are proposed. The structural parameters, dipole moments, conformational stability, and vibrational frequencies have been determined from ab initio calculations. The predicted conformational stability is consistent with the experimental results. These experimental and theoretical results are compared to the corresponding quantities of some similar molecules. (C) 2000 Elsevier Science B.V.
- Durig,Gounev,Zhen,Drew,Shen,Guirgis
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Read Online
- Solvent effects and activation parameters in the competitive cleavage of C-CN and C-H bonds in 2-methyl-3-butenenitrile using [(dippe)NiH]2
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The reaction of [(dippe)NiH]2 with 2-methyl-3-butenenitrile (2M3BN) in solvents spanning a wide range of polarities shows significant differences in the ratio of C-H and C-CN activated products. C-H cleavage is favored in polar solvents, whereas C-C cleavage is favored in nonpolar solvents. This variation is attributed to the differential solvation of the transition states, which was further supported through the use of sterically bulky solvents and weakly coordinating solvents. Variation of the temperature of reaction of [(dippe)NiH]2 with 2M3BN in decane and N,N-dimethylformamide (DMF) allowed for the calculation of Eyring activation parameters for the C-CN activation and C-H activation mechanisms. The activation parameters for the C-H activation pathway were ΔH? = 11.4 ± 5.3 kcal/mol and ΔS? = -45 ± 15 e.u., compared with ΔH? = 17.3 ± 2.6 kcal/mol and ΔS ? = -29 ± 7 e.u. for the C-CN activation pathway. These parameters indicate that C-H activation is favored enthalpically, but not entropically, over C-C activation, implying a more ordered transition state for the former.
- Swartz, Brett D.,Reinartz, Nicole M.,Brennessel, William W.,Garcia, Juventino J.,Jones, William D.
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- AIR-STABLE NI(0)-OLEFIN COMPLEXES AND THEIR USE AS CATALYSTS OR PRECATALYSTS
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The present invention relates to air stable, binary Ni(0)-olefin complexes and their use in organic synthesis.
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Page/Page column 23
(2021/02/05)
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- Ni(4?Tbustb)3: A robust 16-electron Ni(0) olefin complex for catalysis
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Sixteen-electron Ni(0) complexes bearing trans-stilbene derivative ligands have been shown to display a high degree of stability toward oxidation in the solid state. A structural analysis of a unique family of tris Ni(0) stilbene complexes revealed a remarkable effect of the steric hindrance of the substituents at the para position of the stilbene unit to temperature, oxidation, and degradation in solution. From these analyses, Ni(4?tBustb)3 arose as a long-term air-, bench-. and temperature-stable Ni(0) complex. Importantly, Ni(4?tBustb)3 presents faster kinetic profiles and a broader scope as a Ni(0) source, thus outperforming the previously described Ni(4?CF3stb)3 in a variety of relevant Ni-catalyzed transformations.
- Nattmann, Lukas,Cornella, Josep
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supporting information
p. 3295 - 3300
(2020/10/12)
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- PROCESS FOR ISOMERIZATION OF CIS-2-PENTENENITRILE TO 3-PENTENENITRILES
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Discontinuous or continuous isomerization of cis-2-pentenenitrile to 3-pentenenitriles, comprises isomerizing cis-2-pentenenitrile with tertiary amine compounds (I) and their mixtures. Discontinuous or continuous isomerization of cis-2-pentenenitrile to 3-pentenenitriles, comprises isomerizing cis-2-pentenenitrile with tertiary amine compounds of formula (I) and their mixtures. R1, R2 : H, linear or branched 1-5C-alkyl, 5-7C-cycloalkyl, hydroxyethyl or ethylene group bridging two N. [Image].
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Paragraph 0066-0068
(2017/01/02)
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- δ-deuterium isotope effects as probes for transition-state structures of isoprenoid substrates
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The biosynthetic pathways to isoprenoid compounds involve transfer of the prenyl moiety in allylic diphosphates to electron-rich (nucleophilic) acceptors. The acceptors can be many types of nucleophiles, while the allylic diphosphates only differ in the number of isoprene units and stereochemistry of the double bonds in the hydrocarbon moieties. Because of the wide range of nucleophilicities of naturally occurring acceptors, the mechanism for prenyltransfer reactions may be dissociative or associative with early to late transition states. We have measured δ-secondary kinetic isotope effects operating through four bonds for substitution reactions with dimethylallyl derivatives bearing deuterated methyl groups at the distal (C3) carbon atom in the double bond under dissociative and associative conditions. Computational studies with density functional theory indicate that the magnitudes of the isotope effects correlate with the extent of bond formation between the allylic moiety and the electron-rich acceptor in the transition state for alkylation and provide insights into the structures of the transition states for associative and dissociative alkylation reactions.
- Choi, Seoung-Ryoung,Breugst, Martin,Houk, Kendall N.,Poulter, C. Dale
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p. 3572 - 3580
(2014/05/06)
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- Process for Isomerization of CIS-2-Pentenenitrile to 3-Pentenenitriles
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The present invention relates to an improved process for batchwise or continuous isomerization of cis-2-pentenenitrile to 3-pentenenitriles in the presence of 1,4-diazabicyclo[2.2.2]octane as catalyst.
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Paragraph 0051
(2013/11/06)
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- Highly efficient nickel-catalyzed 2-methyl-3-butenenitrile isomerization: Applications and mechanistic studies employing the TTP ligand family
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A series of sterically and electronically fine-tuned, chelating diphosphine ligands were synthesized. The ligands are analogues of Triptyphos (TTP, 1), all based upon a variably 9,10-two-carbon-bridged 9,10-dihydroanthracene scaffold. These new TTP-type l
- Tauchert, Michael E.,Warth, Daniel C. M.,Braun, Sebastian M.,Gruber, Irene,Ziesak, Alexandra,Rominger, Frank,Hofmann, Peter
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experimental part
p. 2790 - 2809
(2011/07/29)
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- The influence of carbon laydown on selectivity in the hydrogenation of pentenenitriles over supported-nickel catalysts
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Pentenenitriles contain two-reducible functionalities: a carbon-carbon double bond and a nitrile group, either of which may undergo hydrogenation during reaction. In this work we show how the deposition of hydrocarbonaceous material on the catalyst surface during pentenenitrile hydrogenation over 16 wt.% Ni/Al2O3 and 10 wt.% Ni/SiO2 catalysts has a significant impact on the observed catalytic activity and selectivity. The role of carbon laydown in controlling catalytic performance in this system has been evaluated through activity measurements and mechanistic studies employing a Tapered Element Oscillating Microbalance (TEOM) and a conventional flow-through reactor. TEOM data indicating the deposition of carbonaceous material during reaction are correlated with kinetic analysis which provides a description of catalyst deactivation in terms of the deactivation of groups of active sites. Specifically five distinct active sites are shown to exist on Ni/Al 2O3 including a hydrogenation site on the support, which is not present in the case of Ni/SiO2. The nature and strength of these sites are discussed. Furthermore, deuteration studies provide mechanistic insights suggesting that the hydrogenation reaction proceeds via a cyclic intermediate. The reported data identify a correlation between mass laydown on specific active sites and deactivation, thereby demonstrating the influence of hydrocarbonaceous deposits on selectivity. Both the location and the nature of such deposits are crucial in determining its influence on reaction.
- McGregor, James,Canning, Arran S.,Mitchell, Scott,Jackson, S. David,Gladden, Lynn F.
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experimental part
p. 192 - 200
(2010/11/17)
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- PROCESS FOR MAKING 3-PENTENENITRILE BY HYDROCYANATION OF BUTADIENE
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The invention provides a continuous process for the production of 3-pentenenitrile comprising: (a) contacting, in a reaction zone, a hydrogen cyanide-containing feed, a butadiene-containing feed, and a catalyst precursor composition, wherein the catalyst
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Page/Page column 6; 6-7; 7
(2008/06/13)
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- Isomerization of 2-methyl-3-butenenitrile with (bis-diphenylphosphinoferrocene)nickel compounds: Catalytic and structural studies
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The catalytic isomerization of 2-metyl-3-butenenitrile to 3-pentenenitrile was carried out by (dppf)Ni species (dppf = bis-diphenylphosphinoferrocene) in the absence and the presence of Lewis acids. Studies in solution reveal the intermediacy of Ni(II) allyl complexes. Addition of Lewis acids such as BEt3 allow the crystallization and full characterization of the latter by X-ray diffraction studies.
- Acosta-Ramírez, Alberto,Mu?oz-Hernández, Miguel,Jones, William D.,García, Juventino J.
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p. 3895 - 3901
(2007/10/03)
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- METHOD FOR PRODUCING 3-PENTENENITRILE
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The invention relates to a method for producing 3-pentenenitrile, said method being characterised by the following steps: (a) 1,3-butadiene is reacted with hydrogen cyanide on at least one catalyst to obtain a flow (1) containing 3-pentenenitrile, 2-methyl-3-butenenitrile, the at least one catalyst, and 1,3-butadiene; (b) the flow (1) is distilled in a column to obtain a top product flow (2) rich in 1,3-butadiene, and a bottom product flow (3) that is poor in 1,3-butadiene and contains 3-pentenenitrile, the at least one catalyst, and 2-methyl-3-butenenitrile; (c) the flow (3) is distilled in a column to obtain a top product flow (4) containing 1,3-butadiene, a flow (5) in a side-tap of the column, containing 3-pentenenitrile and 2-methyl-3-butenenitrile, and a bottom product flow (6) containing the at least one catalyst; and (d) the flow (5) is distilled to obtain a top product flow (7) containing 2-methyl-3-butenenitrile, and a bottom product flow (8) containing 3-pentenenitrile.
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Page/Page column 35-38; sheet 5
(2008/06/13)
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- PRODUCTION OF 3-PENTENENITRILE FROM 1,3-BUTADIENE
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The invention relates to a method for producing 3-pentenenitrile by means of the hydrocyanation of 1,3-butadiene, whereby 1,3-butadiene is reacted with hydrogen cyanide in the presence of at least one catalyst, and the resulting flow is purified by distillation, the bottom temperature not exceeding 140 °C during the distillation.
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Page/Page column 25-29; sheet 2
(2008/06/13)
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- METHOD FOR PRODUCING LINEAR PENTENENITRILE
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The invention relates to a method for producing 3-pentenenitrile, characterised by the following steps: (a) isomerisation of an educt stream containing 2-methyl-3-butenenitrile on at least one dissolved or dispersed isomerisation catalyst to form a stream (1), which contains the isomerisation catalyst(s), 2-methyl-3-butenenitrile, 3-pentenenitrile and (Z)-2-methyl-2-butenenitrile; (b) distillation of the stream (1) to obtain a stream (2) as the overhead product, which contains 2-methyl-3-butenenitrile, 3-pentenenitrile and (Z)-2-methyl-2-butenenitrile and a stream (3) as the bottom product, which contains the isomerisation catalyst(s); (c) distillation of the stream (2) to obtain a stream (4) as the overhead product, which is enriched with (Z)-2-methyl-2-butenenitrile in comparison to stream (2), (in relation to the sum of all pentenenitriles in stream (2)) and a stream (5) as the bottom product, which is enriched with 3-pentenenitrile and 2-methyl-3-butenenitrile in comparison to stream (2), (in relation to the sum of all pentenenitriles in stream (2); (d) distillation of stream (5) to obtain a stream (6) as the bottom product, which contains 3-pentenenitrile and a stream (7) as the head product, which contains 2-methyl-3-butenenitrile.
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Page/Page column 72-76; sheet 2
(2008/06/13)
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- HOMOGENEOUS ISOMERIZATION OF CIS-2-PENTENE NITRILE TO FORM 3-PENTENE NITRILE
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The invention relates to a method for isomerization of pentene nitrile in an educt flow, wherein isomerization is performed on a homogeneously dissolved catalyst.
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Page/Page column 9-11
(2008/06/13)
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- ISOMERISATION OF CIS-2-PENTENENITRILE TO FORM 3-PENTENENITRILE IN A REACTIVE DISTILLATION
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The invention relates to a method for the isomerisation of pentenenitrile in an educt flow. Said isomerisation is carried out on a heterogeneous catalyst in a distillation column, such that during the isomerisation, the isomerisation educt is enriched by distillation in relation to the isomerisation product in the reaction column of the distillation column.
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Page/Page column 13-14
(2008/06/13)
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- METHOD FOR THE ISOMERIZATION OF CIS-2-PENTENENITRILE TO FORM TRANS-3-PENTENENITRILE
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The invention relates to a method for the isomerization of 2-pentenenitrile to form trans-3-pentenenitrile in the presence of aluminium oxide as a catalyst. The invention is characterised in that the BET surface of the aluminium oxide is at least 50 m2/g.
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- Sterically demanding diphosphonite ligands - Synthesis and application in nickel-catalyzed isomerization of 2-methyl-3-butenenitrile
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The synthesis of a novel class of sterically demanding diphosphonites 1-8, based on rigid backbones, is described. The starting materials are all commercially available and the methodology allows for a modular approach. All ligands have been fully characterized, including an X-ray crystal structure for compound 1, 4,5-bis{di[(2-terr-butyl)phenyl]phosphonito}-9,9-dimethylxanthene. The coordination of these diphosphonite ligands towards Ni(II) and Ni(0) precursors is investigated, both by NMR spectroscopy as well as X-ray crystallography and compared with the behaviour of diphosphine ligands such as Xantphos. The molecular structure for complex 9, trans-[NiBr2(1)] is described in detail. The nickel-catalyzed isomerization of 2-methyl-3- butenenitrile to 3-pentenenitrile is studied, a relevant step in the industrially important hydrocyanation of butadiene (the DuPont adiponitrile process). Good activities and selectivities to the desired 3-pentenenitrile are obtained in this reversible C-C bond activation reaction.
- Van Der Vlugt, Jarl Ivar,Hewat, Alison C.,Neto, Samuel,Sablong, Rafael,Mills, Allison M.,Lutz, Martin,Spek, Anthony L.,Mueller, Christian,Vogt, Dieter
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p. 993 - 1003
(2007/10/03)
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- PHOSPHONITE LIGANDS AND THEIR USE IN HYDROCYANATION
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Disclosed herein are processes for hydrocyanation and isomerization of olefins by using at least one multidentate phosphonite ligands, including organometallic phosphonite ligands with a Group VIII metal or Group VIII metal compound, and optionally, a Lewis acid promoter.
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Page/Page column 11
(2008/06/13)
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- HYDROCYANATION PROCESSES AND MULTIDENTATE PHOSPHITE LIGAND AND NICKEL CATALYST COMPOSITIONS THEREFOR
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A process for hydrocyanation of an aliphatic monoethylenically unsaturated compound, in which the ethylenic double bond is not conjugated to any other unsaturated group in the molecule, which process uses a catalyst composition comprising a zero-valent nickel and a multidentate phosphite ligand in the presence of a Lewis acid promoter.
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- Catalyst comprising at least one phosphonite ligand based nickel (O) complex and method for the production of nitriles
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A catalyst comprising at least one nickel(0) complex which comprises at least one mono-, bi- or multidentate phosphonite ligand of the formula I or salts and mixtures thereof, is prepared as described, and the catalysts are used to prepare mixtures of monoolefinic C5mononitriles with nonconjugated C═C and C≡N bonds by catalytic hydrocyanation of butadiene or of a 1,3-butadiene-containing hydrocarbon mixture in the presence of a catalyst of this type.
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- Hydrocyanation processes and multidentate phosphite ligand and nickel catalyst compositions therefor
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A process for hydrocyanation of an aliphatic monoethylenically unsaturated compound, in which the ethylenic double bond is not conjugated to any other unsaturated group in the molecule, or a monoethylenically unsaturated compound in which the ethylenic double bond is conjugated to an ester group, which process uses a catalyst composition comprising a zero-valent nickel and a multidentate phosphite ligand in the presence of a Lewis acid promoter.
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- Cryptocope rearrangement of 1,3-dicyano-5-phenyl-4,4-d2-hexa-2,5-diene. Chameleonic or centauric?
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The 'centauric' model for evaluation of the effect of radical- stabilizing perturbations on the Cope rearrangement conjectures independent action of substituents that make conflicting electronic demands on the two halves of the transition region. The present test of this conjecture compares 1,3-dicyano-[5-protio]-hexa-1,5-diene (1(H)) and 2-phenylhexa-1,5-diene, with 1,3-dicyano-5-phenylhexa-1,5-diene (1(Ph)). Thermochemical information required for a proper comparison includes new data of the van't Hoff type on conjugative interaction of cyano with the carbon-carbon double bond, reevaluation of the radical-stabilizing potential of the cyano group on secondary and allyl radicals, comparison with the (reevaluated) stabilizing effect of cyano in 'nodal' positions of the Cope transition region, and determination of the enthalpy and entropy of activation of the cryptoCope rearrangement of otherwise Cope-incompetent, thermodynamically more stable hexa-2,5-dienes related by prototropy to the Cope-competent hexa-1,5-dienes above. The 'chameleonic' model is concluded to be unsatisfactory, while the 'centauric' is in better, if not complete, accord with experiment.
- Doering, W. Von E.,Wang, Yonghui
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p. 10967 - 10975
(2007/10/03)
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- Hydrocyanation processes and multidentate phosphite ligand and nickel catalyst compositions thereof
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A process for hydrocyanation of an aliphatic monoethylenically unsaturated compound, in which the ethylenic double bond is not conjugated to any other unsaturated group in the molecule, which process uses a catalyst composition comprising a zero-valent nickel and a multidentate phosphite ligand in the presence of a Lewis acid promoter.
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- Processes and catalyst compositions for hydrocyanation of monoolefins
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Processes for hydrocyanation of nonconjugated acyclic aliphatic monoolefins, monoolefins conjugated to an ester group, or monoolefins conjugated to a nitrile group which utilize a catalyst precursor composition comprising a bidentate phosphite ligand and zero-valent nickel preferably in the presence of a Lewis acid prompter. Catalyst precursor compositions are also disclosed.
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- Hydrocyanation process and multidentate phosphite and nickel catalyst composition therefor
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A process for hydrocyanation of an aliphatic monoethylenically unsaturated compound, in which the ethylenic double bond is not conjugated to any other unsaturated group in the molecule, or a monoethylenically unsaturated compound in which the ethylenic double bond is conjugated to an ester group, which process uses a catalyst composition comprising a zero-valent and a multidentate phosphite ligand in the presence of a Lewis acid promoter.
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- Die Isocyanid-Cyanid-Umlagerung - Mechanismus und praeparative Anwendung
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Bis vor kurzem war die Isocyanid-Cyanid-Umlagerung hauptsaechlich als Beispiel fuer eine unimolekular verlaufende Gasphasenreaktion bekannt und nur fuer einfache Systeme kinetisch untersucht.Kinetikstudien in Loesung wurden erst moeglich, als man eine ueberlagerte, zum gleichen Produkt fuehrende Radikalkette erkannte und diese inhibieren konnte.Die Geschwindigkeit der Isomerisierung erwies sich als kaum von der Struktur und von Substituenten abhaengig.Allenfalls starke sterische Hinderung in drei Dimensionen wie in tris-α-substituierten Triptylcylisocyaniden fuehrt zu einer deutlichen Erhoehung der Aktivierungsenthalpie.Die Ergebnisse lassen sich mit einem rein sigmatropen Mechanismus deuten und sind damit in Einklang mit Voraussagen aus ab-initio-Rechnungen.Auch praeparativ laesst sich diese Umlagerung inzwischen nutzen.Bei der Blitzpyrolyse sind die Ausbeuten an Cyanid nahezu quantitativ.Allylisocyanide reagieren ohne Allylisomerisierung und optisch aktive Isocyanide unter vollstaendiger Retention.Die Umlagerung kann sowohl Bestandteil wirtschaftlich interessanter Synthesen, z.B. der Entzuendungshemmer Ibuprofen und (S)-Naproxen, sein als auch beim Aufbau optisch aktiver β-Acyloxycyanide, die nuetzliche Synthesebausteine sind, aus optisch aktiven α-Aminosaeuren helfen.
- Ruechardt, Christoph,Meier, Michael,Haaf, Klaus,Pakusch, Joachim,Wolber, Erwin K. A.,Mueller, Barbara
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p. 907 - 915
(2007/10/02)
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- Kinetics and Regioselectivity of Ring Opening of Substituted Cyclopropylmethyl Radicals
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Accurate analysis of the mixture of hydroxylamines 8 formed when suitable peroxides 4 undergo homolysis in the presence of the nitroxyl radical 1,1,3,3-tetramethylisoindolin-2-yloxy (T) has afforded rate constants for ring opening of the cyclopropylmethyl radicals 2a, 2c, 2dcis, 2dtrans, and 2e and cyclization of the but-3-enyl radicals 1a, 1c, and 1d.The presence of methyl substituents enhances the rates both of cyclization and of ring opening to give primary radicals.In the case of the trans-2-methylcyclopropyl radical, 2dtrans, this effect leads to preferential formation of the less thermodynamically stable possible product, 1d, below about 60 deg C.In general, the effects of substituents support the view that the transition structure for the cyclopropylmethyl-butenyl radical interconversion is dipolar.Combination of data from four sets of workers using three different kinetic techniques affords the following recommended Arrhenius equation for the cyclopropylmethyl radical clock reaction: log k1(2a) = 13.31 - 7.6/2.3RT.
- Beckwith, Athelstan L. J.,Bowry, Vincent W.
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p. 2681 - 2688
(2007/10/02)
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- The Stereochemistry of Organometallic Compounds. XXVIII The Nickel-Catalysed Addition of Hydrogen Cyanide to Aliphatic Dienes
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Reaction of hydrogen cyanide with a wide range of aliphatic dienes in the presence of nickel(0) catalysts leads to rearrangement of the diene and formation of β,γ-unsaturated nitriles in moderate to very high yields.The mechanism of reaction is discussed in terms of ?-allyl-nickel intermediates.
- Campi, Eva M.,Elmes, Patricia S.,Jackson, W. Roy,Lovel, Craig G.,Probert, Michael K. S.
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p. 1053 - 1061
(2007/10/02)
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- The Synthetic Potential of the Isocyanide-Cyanide Rearrangement
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Excellent chemical and optical yields (>96percent retention) of cyanides are achieved by vapor phase thermolysis or short contact flow thermolysis of isocyanides. trans-2-Butenyl isocyanide rearranges without concomitant allylic isomerization to trans-2-butenyl cyanide.Optically active 1-(formyloxymethyl)-2-phenylethyl cyanide is obtained from optically active L-phenylalanine as a new type of chiral pool synthon.
- Meier, Michael,Ruechardt, Christoph
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- Manufacture of organic nitriles
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A process for the manufacture of adiponitrile is described by reacting butadiene with hydrogen cyanide and a catalyst which is a complex of a copper salt and an organic nitrile to form 3-pentenenitrile, which is then hydrocyanated to adiponitrile in which the solvent and sole nitrile complexing agent for the copper is 3-methylglutaronitrile or a mixture of 3-methylglutaronitrile with 2-ethylsuccindinitrile or with 2-ethylsuccindinitrile and adiponitrile.
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- Manufacture of 3-pentene nitrile
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A process for the manufacture of 3-pentene-nitrile is disclosed by reacting butadiene and hydrogen cyanide in the presence of a cuprous halide catalyst with an organic nitrile, the reactants present in specified proportions, the process being conducted in the presence of a further halide or mixtures of halides from an inorganic source of halide in addition to the amount from the cuprous halide.
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- Manufacture of organic nitriles
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Olefins are converted to nitriles by reacting with hydrogen cyanide in the presence of an organic thiol or sulphide and a catalytic amount of a cuprous salt which is soluble therein; especially for making 3-pentene nitrile from butadiene.
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