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.
Vibrational Overtone Activation of the Isomerization of Methyl Isocyanide
Hassoon, Salah,Rajapakse, Nandani,Snavely, Deanne L.
, p. 2576 - 2581 (1992)
The photoisomerization of methyl isocyanide to form acetonitrile induced by excitation into the fourth (ca. 1 kcal/mol above the activation barrier) and fith (ca. 8 kcal/mol above the barrier) C-H stretch vibrational overtones is reported.The ratio of the collisional deactivation rate constant to be unimolecular rate coefficient, k(ε), was determined by a Stern-Volmer analysis plotting the inverse apparent rate constant against the total pressure.The unimolecular rate coefficients increase monotonically with increasing excitation energies across the rotational band contours.The experimental k(ε) agree with RRKM calculated values.The Stern-Volmer plots are nonlinear at low pressure: the fourth overtone excitation shows negative curvature (decreasing slope with increasing pressure) and the fifth overtone shows positive curvature (increasing slope with increasing pressure).The magnitude and direction of this curvature agree well with the calculated Stern-Volmer plots in earlier work using a master equation simulation.In these vibrational overtone activation studies, the collisional deactivation efficiency of argon is 0.3 of that of the self-collider.
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.
An unusual coordination mode of acetylide ligands: synthesis of tetranuclear copper(I) complexes containing μ3-η1acetylide ridging ligands. Crystal structure of 3-η1-CCPh)-(Ph2Ppy-P)>4 (Ph2Ppy=2-(diphenylphosphine)pyridine)
Gamasa, Pilar M.,Gimeno, Jose,Lastra, Elena,Solans, Xavier
, p. 277 - 286 (1988)
The preparation and properties of novel tetranuclear copper(I) complexes of the type CR)(L-L)4 (L-L = 2-(diphenylphosphine)pyridine (Ph2Ppy) R = tBu, Ph; L-L = bis(diphenylphosphino)methane (dppm), R = Ph are described.The crystal structure of 3-η1-CCPh)(Ph2Ppy-P)>4 has been determined by X-ray diffraction.Crystals are monoclinic, space group C2/c with Z=4 in a unit cell of dimensions a 14.859(3), b 24.405(4), c 23.279(4) Angstroem and β 95.35(2) deg; refinement gave R = 0.056 for 3586 reflections with I>=2.5?(I).The molecule consists of a tetrahedral cluster of copper atoms bearing four μ3-η1 phenylacetylide and four monodentate P-bonded 2-(diphenylphosphine)pyridine ligands (Ph2Ppy-P).IR, 1H and 31P-NMR data are discussed.
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.
Ammoxidation of ethylene over low and over-exchanged Cr-ZSM-5 catalysts
Ayari,Mhamdi,álvarez-Rodríguez,Guerrero Ruiz,Delahay,Ghorbel
, p. 132 - 140 (2012)
Catalytic performances of Cr-ZSM-5 catalysts (5 wt.% of Cr, Si/Al = 26), prepared by solid-state reaction and aqueous exchange, from Cr nitrate and Cr acetate precursors, were evaluated in the selective ammoxidation of ethylene into acetonitrile in the temperature range 425.500 °C. Catalysts were characterized by chemical and thermal analysis, XRD, N2 physisorption, 27Al MAS NMR, TEM, UV-vis DRS, Raman, DRIFTS and H2-TPR. Characterization results shown that solid-state exchange was favorable for Cr2O3 formation, while exchanging chromium in aqueous phase led, essentially, to Cr(VI) species. Catalysts were actives and selectives in the studied reaction, and among them, those, prepared from aqueous exchange, exhibited the highest acetonitrile yields (23±0.5%, at 500 °C). Improved catalytic properties can be correlated with the chromium species nature. In fact, mono/di-chromates and/or polychromate species, sited in the charge compensation positions, were definitively shown, as being, the active sites. Furthermore, during solid-state reaction, the agglomeration of Cr2O3 oxide should be avoided since these species inhibit the catalyst activity.
A double decker type complex: Copper(I) iodide complexation with mixed donor macrocycles via [1:1] and [2:2] cyclisations
Kang, Yunji,Park, In-Hyeok,Ikeda, Mari,Habata, Yoichi,Lee, Shim Sung
, p. 4528 - 4533 (2016)
19-membered and a 38-membered macrocycles obtained as a mixture via respective [1:1] and [2:2] cyclisations were separated and their coordination behaviours with copper(I) iodide were investigated. One of the notable products isolated is a tetranuclear bis(macrocycle) complex with the larger macrocycle adopting a double decker type structure. Furthermore, removal of the lattice solvent molecules in the above complex in air motivates the displacement of the double decker units along the a-axis by sliding in a single-crystal-to-single-crystal manner.
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.
Picosecond Kinetics by Exchange Broadening in the Infrared and Raman. 3. CH3CN.IBr
Cohen, Benyamin,Weiss, Shmuel
, p. 3974 - 3976 (1984)
Spectra of the ν2 and ν3+ν4 bands of CH3CN in the presence of IBr and in CCl4 solution were measured over a range of temperatures.The spectra could be analyzed to reveal the kinetics of the CH3CN + IBr CH3CN.IBr reaction, in the picosecond range.Association and dissociation rate constants were determined and, from them, activation energies and entropies.
