F:Flammable;
75-05-8Relevant articles and documents
Ammoxidation of Ethanol to Acetonitrile over Molecular Sieves
Kulkarni, S. J.,Rao, R. Ramachandra,Subrahmanyam, M.,Rao, A. V. Rama
, p. 273 - 274 (1994)
For the first time, we report the ammoxidation of ethanol over crystalline, microporous silica-aluminophosphate and Y zeolite with >99.0 and 40.0percent m/m yields of acetonitrile respectively.
Cationic Titanium(IV) Complexes via Halide Abstraction from : Crystal and Molecular Structure of 3*2MeCN
Willey, Gerald R.,Butcher, Mark L.,McPartlin, Mary,Scowen, Ian J.
, p. 305 - 310 (1994)
Treatment of (cp=η5-C5H5) with SbCl5 as chloride abstractor in acetonitrile provided hexachloroantimonate(V) salts of (1+), (2+) and (3+) respectively.With 1:1 stoichiometry red-brown crystals of 1 are obtained and with 1:2 stoichiometry light blue crystals of 2 2.Complete removal of chloride ion from requires a six-fold excess of SbCl5 when purple-blue crystals of 3 3 can be isolated.These products were characterised by analytical and spectroscopic (IR, 1H NMR) data and, in the case of 3, by a crystal structure determination.Proton NMR studies indicate the presence of intermediate halide-bridged species in solution during the sequential halide abstractions 1 --> 2 --> 3.Crystals of complex 3, obtained as the bis(solvate) from recrystallisation in acetonitrile, are monoclinic and X-ray structural analysis confirmed the formulation.The crystal structure a=19.650(4), b=19.182(4), c=12.958(3) Angstroem, β=91.612(3) deg, Z=4, R=0.0386, R'=0.0406> shows discrete cations and anions and a pseudo-octahedral co-ordination sphere for the Ti(IV).A significant trans influence of the cyclopentadienyl ligand affects Ti-N bond lengths in the complex.
Structure, stability, and generation of CH3CNS
Krebsz, Melinda,Hajgato, Balazs,Bazso, Gabor,Tarczay, Gyoergy,Pasinszki, Tibor
, p. 1686 - 1693 (2010)
The unstable acetonitrile N-sulfide molecule CH3CNS has been photolytically generated in inert solid argon matrix from 3,4-dimethyl-1,2,5- thiadiazole by 254-nm UV irradiation, and studied by ultraviolet spectroscopy and mid-infrared spectroscopy. The molecule is stable in the matrix to 254-nm UV irradiation, but decomposes to CH3CN and a sulfur atom when broad-band UV irradiation is used. Chemiluminescence due to S2 formation from triplet sulfur atoms was detected on warming the matrix to ～20-25K. The ground-state structure and potential uni- and bimolecular reactions of CH3CNS are investigated using B3LYP, CCSD(T), and MR-AQCC quantum-chemical methods. CH3CNS is demonstrated to be stable under isolated conditions at room temperature, i.e. in the dilute gas phase or in an inert solid matrix, but unstable owing to bimolecular reactions, i.e. in the condensed phase. CSIRO 2010.
Ground-state rotational spectrum of CH3NC...HCN and the nature of hydrogen bonds involving triply-bonded carbon
Legon, A. C.,Thorn, J. C.
, p. 449 - 458 (1992)
The ground state rotational spectra of the hydrogen-bonded species CH3NC...HCN and CH3NC...DCN have been studied using the technique of pulsed-nozzle Fourier-transform microwave spectroscopy.The spectra were of the symmetric top type and their analysis led to the rotational constants B0 = 969.0435(4) MHz and 964.7530(5) MHz for the parent and deuterated molecule, respectively.The centrifugal distortion constants, DJ and DJK, were established to be 0.369(7) kHz for CH3NC...HCN, and 0.356(8) kHz and 39.4(2) kHz for the deuterium species, while the corresponding (14)N-nuclear coupling constants were χ(14N) = -4.23(11) MHz and -4.5(1) MHz.Analysis of the centrifugal constants DJ using a model of C3v symmetry with the atoms arranged in the order H3CNC...HCN gave the quadratic force constant associated with stretching of the hydrogen bond as 9.3(1) N m-1 and 9.7(1) N m-1 in CH3NC...HCN and CH3NC...DCN, respectively.The distances in these isotopomers between the carbon nuclei adjacent to the hydrogen bond r(C...C), were found to be 3.433(3) Angstroem and 3.420(3) Angstroem, when using a model that compensates for the contributions of the intermolecular bending modes to the zero-point motion.
Lynn,Yankwich
, p. 790 (1961)
Synthesis and ligand-based mixed valency of cis- and trans-CrIII(X4SQ)(X4Cat)(L)n (X = Cl and Br, n = 1 or 2) complexes: Effects of solvent media on intramolecular charge distribution and ligand dissociation of CrIII(X4SQ)3
Chang, Ho-Chol,Mochizuki, Katsunori,Kitagawa, Susumu
, p. 4444 - 4452 (2002)
The treatment of CrIII(X4SQ)3 (SQ = o-semiquinonate; X = Cl and Br) with acetonitrile affords trans CrIII(X4SQ)- (X4Cat)(CH3CN)2 (X = Cl (1) and Br (2)). In the presence of 2,2′-bipyridine (bpy) or 3,4,7,8-tetramethyl-1,10-phenanthrene (tmphen), the reaction affords CrIII(X4SQ)(X4Cat)(bpy) ·nCH3CN (X = Cl, n = 1 (3); X = Br, n = 0.5 (4)) or CrIII(X4SQ)(X4Cat)(tmphen) (X = Cl (5) and Br (6)), respectively. All of the complexes show a ligand-based mixed-valence (LBMV) state with SQ and Cat ligands. The LBMV state was confirmed by the presence of the interligand intervalence charge-transfer band. Spectroscopic studies in several solvent media demonstrate that the ligand dissociation included in the conversion of CrIII(X4SQ)3 to 1-6 occurs only in solvents with relatively high polarity. On the basis of these results, the effects of solvent media were examined and an equilibrium, CrIII(X4SQ)3 ? CrIII(X4BQ)(X4SQ)(X4Cat) (BQ = o-benzoquinone), is proposed by assuming an interligand electron transfer induced by solvent polarity.
A reaction pathway for the ammoxidation of ethane and ethylene over Co-ZSM-5 catalyst
Li, Yuejin,Armor, John N.
, p. 495 - 502 (1998)
The ammoxidation of ethane and ethylene to acetonitrile was studied over a Co-ZSM-5 catalyst with an emphasis on the reaction pathway. We found that the adsorption of ammonia on Co-ZSM-5 is stronger than that on H-ZSM-5. CzH4 adsorption is weak and readily desorbs below 300°C. While the adsorption of C2H3N (a reaction product) is very strong in He, its desorption is accelerated with the presence of NH3. With a specially designed temperature programmed experiment (reaction between the adsorbed NH3 and gaseous C2H4/O2/He mixture), we observed C2H5NH2 as a reactive intermediate, and this intermediate was demonstrated to be readily converted to C2H3N under the ammoxidation reaction conditions. A detailed pathway is offered, whereby C2H4 is thought to add on an adsorbed NH3, forming an adsorbed ethylamine which is subsequently dehydrogenated to form C2H3N. We further speculate that an oxidative environment N2 comes from N-N pairing between the adsorbed NH3 and an amine (both on a single Co2+ site).
Thompson, H. W.
, p. 344 - 352 (1941)
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Hammer,Swann
, p. 325 (1949)
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Acetonitrile Formation from Ethylene and Ammonia over Zn2+ and Cd2+ Exchanged Y-zeolites
Takahashi, Nobuo,Minoshima, Hiroshi,Iwadera, Hiroyuki
, p. 1323 - 1324 (1994)
Zn2+ and Cd2+ exchanged Y-zeolites are found to be active for acetonitrile formation from ethylene and ammonia.Their catalytic activities are much higher than that on Al2O3, which has been known to be an active catalyst for this reaction.
Laser photochemistry and transient Raman spectroscopy of silyl-substituted Fischer-type carbene complexes
Rooney, A. Denise,McGarvey, John J.,Gordon, Keith C.,McNicholl, Ruth-Anne,Schubert, Ulrich,Hepp, Wolfgang
, p. 1277 - 1282 (1993)
Pulsed laser irradiation of the silyl-substituted carbene complexes (CO)5W=C(XR)SiPh3 (XR = NC4H8 (1); = OEt (2)) in various solvents has been investigated using transient absorbance and time-resolved resonance Raman scattering as monitoring techniques. Irradiation of (1) in noncoordinating or weakly-coordinating solvents at 355 nm within the ligand field absorption band results in the rapid formation, within the laser pulse duration, of a permanent photoproduct. Saturation of the irradiated solution with CO results in regeneration of the starting complex 1. IR and Raman spectral data suggest that the photoproduct is the internally stabilized 16-electron species (CO)4W=C(NC4H8)SiPh3. The observations are discussed in relation to the previously reported formation of the same 16-electron species by thermolysis of 1. When the irradiation is carried out in CH3CN as solvent, UV-visible evidence suggests formation of the photosubstituted species (CO)4(CH3CN)W=C(NC4H8)SiPh 3. No photoactivity, either transient or permanent, is seen in any solvent when the irradiation is carried out at 416 nm, a wavelength which falls within the MLCT absorption region of 1. When the ethoxy-substituted carbene complex 2 is irradiated in either the LF or MLCT absorption regions a transient species forms rapidly, within the laser pulse duration, and decays on a time scale of several μs, with a lifetime dependent on solvent polarity but independent of CO concentration in solution. Time-resolved resonance Raman studies in which the sample is photolyzed at 355 nm and probed by means of a delayed pulse at 406 nm show the formation and decay of a transient consistent with the flash photolysis results. The data are interpreted in terms of photoinduced anti-syn isomerization of 2 about the Ccarbene-O bond.
Experimental and ab Initio Theoretical Study of the Kinetics of Rearrangement of Ketene Imine to Acetonitrile
Doughty, Alan,Bacskay, George B.,Mackie, John C.
, p. 13546 - 13555 (1994)
When heated by reflected shock waves to temperatures between 1400 and 1700 K at pressures of approximately 12-15 atm, mixtures of acetonitrile in argon (0.4-7 mol percent) exhibit strong banded absorption in the ultraviolet region between 320 and 250 nm.The carrier of the absorption spectrum is ketene imine, H2C=C=NH.Time-resolved spectra of ketene imine have been recorded with exposure times between 100 and 200 μs using a charge-coupled device (CCD) with an imaging spectrograph.Through the use of the technique of pixel binning, temporal profiles of formation and equilibration of ketene imine have been obtained with a time resolution of 24 μs.The rearrangement of ketene imine acetonitrile has been studied using ab initio quantum chemical techniques.The calculations predict the rate-determining step in the rearrangement process to be the 1,2-hydrogen transfer of the imine hydrogen to the adjacent carbon atom to produce vinyl nitrene.With the aid of the ab initio results, the experimental rate data for the reaction ketene imine -> acetonitrile have been extrapolated to the high-pressure limit, yielding the rate constant expression k = 1013.4(+/-0.5) exp(-294(+/-14) kJ mol-1/RT) s-1.
One Step Synthesis of Acetonitrile from Ethanol via Ammoxidation over Sb-V-P-O/Al2O3 Catalyst
Reddy, Benjaram M.,Manohar, Basude
, p. 234 - 235 (1993)
Selective synthesis of acetonitrile in one step from ethanol by ammoxidation is reported, for the first time, using alumina supported and antimony promoted vanadium phosphorus oxide catalyst.
Thermal Explosions of Methyl Isocyanide in Spherical Vessels
Clothier, P. Q. E.,Glionna, M. T. J.,Pritchard, H. O.
, p. 2992 - 2996 (1985)
An improved set of measurements, including a wide variety of consistency tests, on the thermal explosion of methyl isocyanide in spherical vessels from 0.3 to 12.6 L at 350 deg C is presented.We also report an accidental explosion which took place with liquid methyl isocyanide at room temperature.
Lynn, K. R.,Yankwich, P. E.
, p. 1719 - 1720 (1960)
Conversion of methane to acetonitrile over GaN catalysts derived from gallium nitrate hydrate co-pyrolyzed with melamine, melem, or g-C3N4: the influence of nitrogen precursors
Chen, Chi-Liang,Chen, Chin-Han,Huang, Ai-Lin,Lee, Jyh-Fu,Lin, Yu-Chuan,Trangwachirachai, Korawich
, p. 320 - 331 (2022/01/19)
Co-pyrolyzing gallium nitrate hydrate and melamine, melem, or g-C3N4 generates gallium nitride (GaN) for the conversion of methane to acetonitrile (AcCN). The solid-state-pyrolysis-made GaN catalysts exhibited better activity than commercial GaN. Among the as-prepared catalysts, GaN made by using g-C3N4 with a N/Ga ratio of 2 (i.e., GaN-(C3N4)-(2)) was the most attractive: a high initial methane conversion (28.2%), a high initial AcCN productivity (151 μmol gcat?1 min?1), and a 6 h accumulated AcCN yield (5816 μmol gcat?1) were obtained at 700 °C with a space time of 3000 mLCH4?gcat?1?h?1. GaN-(C3N4)-(2) had finely dispersed GaN crystals and enriched amorphous CN species (e.g., sp2 N and C N groups), and both are important in promoting the methane conversion rate. GaN agglomeration, coke deposition, and depleted CN species contributed to the deactivation of the catalyst, and a nitridation–activation process could rejuvenate the activity partially. The analysis of the structure–activity correlation revealed that the accumulated AcCN yield had an inverse trend with respect to the crystallite size of GaN and the sp3/sp2 ratio of the N environment.
Product selectivity controlled by manganese oxide crystals in catalytic ammoxidation
Hui, Yu,Luo, Qingsong,Qin, Yucai,Song, Lijuan,Wang, Hai,Wang, Liang,Xiao, Feng-Shou
, p. 2164 - 2172 (2021/09/20)
The performances of heterogeneous catalysts can be effectively tuned by changing the catalyst structures. Here we report a controllable nitrile synthesis from alcohol ammoxidation, where the nitrile hydration side reaction could be efficiently prevented by changing the manganese oxide catalysts. α-Mn2O3 based catalysts are highly selective for nitrile synthesis, but MnO2-based catalysts including α, β, γ, and δ phases favour the amide production from tandem ammoxidation and hydration steps. Multiple structural, kinetic, and spectroscopic investigations reveal that water decomposition is hindered on α-Mn2O3, thus to switch off the nitrile hydration. In addition, the selectivity-control feature of manganese oxide catalysts is mainly related to their crystalline nature rather than oxide morphology, although the morphological issue is usually regarded as a crucial factor in many reactions.
Lewis Acidic Boranes, Lewis Bases, and Equilibrium Constants: A Reliable Scaffold for a Quantitative Lewis Acidity/Basicity Scale
Mayer, Robert J.,Hampel, Nathalie,Ofial, Armin R.
supporting information, p. 4070 - 4080 (2021/01/29)
A quantitative Lewis acidity/basicity scale toward boron-centered Lewis acids has been developed based on a set of 90 experimental equilibrium constants for the reactions of triarylboranes with various O-, N-, S-, and P-centered Lewis bases in dichloromethane at 20 °C. Analysis with the linear free energy relationship log KB=LAB+LBB allows equilibrium constants, KB, to be calculated for any type of borane/Lewis base combination through the sum of two descriptors, one for Lewis acidity (LAB) and one for Lewis basicity (LBB). The resulting Lewis acidity/basicity scale is independent of fixed reference acids/bases and valid for various types of trivalent boron-centered Lewis acids. It is demonstrated that the newly developed Lewis acidity/basicity scale is easily extendable through linear relationships with quantum-chemically calculated or common physical–organic descriptors and known thermodynamic data (ΔH (Formula presented.)). Furthermore, this experimental platform can be utilized for the rational development of borane-catalyzed reactions.
