16529-66-1Relevant academic research and scientific papers
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
Guirgis,Shen,Drew,Durig
, p. 551 - 554 (2001)
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
Nickel-catalyzed isomerization of 2-methyl-3-butenenitrile to 3-pentenenitrile: A kinetic study using in situ FTIR-ATR spectroscopy
Bini, Laura,Houben, Erwin J.E.,Pidko, Evgeny A.,Müller, Christian,Vogt, Dieter
, p. 271 - 278 (2010)
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.
Rational design of efficient steric catalyst for isomerization of 2-methyl-3-butenenitrile
Han, Minghan,Liu, Kaikai,Wang, Tiefeng
, (2020)
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.
Raman and infrared spectra, conformational stability, normal coordinate analysis, vibrational assignment, and ab initio calculations of trans-3-pentenenitrile
Durig,Gounev,Zhen,Drew,Shen,Guirgis
, p. 221 - 234 (2000)
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.
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
Swartz, Brett D.,Reinartz, Nicole M.,Brennessel, William W.,Garcia, Juventino J.,Jones, William D.
, p. 8548 - 8554 (2008)
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.
AIR-STABLE NI(0)-OLEFIN COMPLEXES AND THEIR USE AS CATALYSTS OR PRECATALYSTS
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Page/Page column 23, (2021/02/05)
The present invention relates to air stable, binary Ni(0)-olefin complexes and their use in organic synthesis.
Ni(4?Tbustb)3: A robust 16-electron Ni(0) olefin complex for catalysis
Nattmann, Lukas,Cornella, Josep
supporting information, p. 3295 - 3300 (2020/10/12)
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.
PROCESS FOR ISOMERIZATION OF CIS-2-PENTENENITRILE TO 3-PENTENENITRILES
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Paragraph 0066-0068, (2017/01/02)
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].
δ-deuterium isotope effects as probes for transition-state structures of isoprenoid substrates
Choi, Seoung-Ryoung,Breugst, Martin,Houk, Kendall N.,Poulter, C. Dale
, p. 3572 - 3580 (2014/05/06)
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.
Process for Isomerization of CIS-2-Pentenenitrile to 3-Pentenenitriles
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Paragraph 0051, (2013/11/06)
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.
