Search

Reaction of the imidazolium N-heterocyclic carbene precursor containing a methyl-substituted pyridyl functionality [HCH3im(CH3py)]PF6, 1, with Ag2O produces the homoleptic Ag(I) complex, [Ag(CH3im(CH3py))2]PF6, 2. In a simple carbene transfer reaction the analogous Au(I) species, [Au(CH3im(CH3py))2]PF6, 3, is formed by treatment of 2 with Au(tht)Cl in dichloromethane. Both 2 and 3 are structurally similar with nearly linearly coordinated NHC ligands. The methyl group appended to the pyridyl ring inhibits rotation of the pyridyl group at room temperature. Addition of AgBF4 to a hot propionitrile solution of 3 followed by crystallization with diethyl ether yields the one-dimensional coordination polymer, {[AuAg(CH3im(CH3py))2(NCCH2CH3)](BF4)2}n, 4, which contains Au-Ag separations of 2.9845(5) and 2.9641(5) A with intermetallic angles of 167.642(14) degrees and 162.081(9) degrees. This material is intensely luminescent in the solid state and exhibits an emission band at 453 nm (lambdaex=350 nm). Nearly colorless [Pd(CH3im(CH3py))2Cl]PF6, 5, is produced upon treatment of 2 with PdCl2(NCC6H5)2. The Pd(II) center in 5 is coordinated to one NHC ligand in a chelate fashion, while the second NHC is bound solely through the carbon center. The X-ray crystal structures of 1-5 are reported.

The photochemical reaction of Tp′Rh(L)(η 2 -PhN=L) [Tp′ = tris-(3,5-dimethyl pyrazolyl)borate, L = CNCH 2 CMe 3 ] to form the coordinatively unsaturated reactive fragment, [Tp′Rh(L)], in the presence of alkylnitriles has been studied. The [Tp′Rh(L)] complex has been shown to selectively activate the primary C H terminus of acetonitrile, propionitrile, butyronitrile, and valeronitrile. The resulting hydrides showed uncharacteristic stability in the presence of C 6 D 6 and their rates of reductive elimination were monitored by 1 H NMR spectroscopy. Competition reactions permit the establishment of the relative stabilities of the activation products.

The coupling reaction of 3-(dimethylamino)acrolein (2a) and ethyl 3-(dimethylamino)acrylate (2b) with arenediazonium chlorides afforded the 2-(arylhydrazono)aldehydes 1a - e. Compounds 1a, b reacted with hydroxylamine hydrochloride to yield the oximes 4a, b. The dioxime 5 was obtained from reaction of 1a with an excess of hydroxylamine hydrochloride. This dioxime afforded the 1,2,3-triazole carbonitrile 6 when treated with acetic anhydride, while α-hydrazono propionitrile 8 was obtained when 5 was treated with acetic acid. Compounds 1a - e could be utilized for the synthesis of a variety of pyrazoles and arylazolopyrimidines via reaction with hydrazines, haloketones and aminoazoles, respectively.

A new ruthenium-based catalytic system for the tail-to-tail dimerization of acrylonitrile has been developed. The addition of carboxylic acids effectively increased the selectivity toward linear dimers, while suppressing the formation of propionitrile, an undesired by-product. Thus, under optimized conditions, the selectivity for linear dimers reached 85.8%. The carboxylic acids are considered to be involved in the protonolysis of the ruthenium–carbon bond of precursors to the product dimers. In accordance with this hypothesis, a linear relationship was observed between the logarithm of the relative rate of dimerization and the p K a value of substituted benzoic acids. It has also been found that the new catalytic system promotes decomposition of 2-cyanoethyl carboxylate, a main Michael addition by-product in the dimerization, to acrylonitrile and the corresponding carboxylic acid under the dimerization conditions. This leads to an increase in the selectivity for linear dimers. A plausible mechanism for the dimerization is proposed.

2D structurally related iron(ii) coordination networks {[Fe(hbtz)2(RCN)2](ClO4)2}∞ featuring, besides tetrazol-2-yl rings in the first coordination sphere, also axially coordinated propionitrile or allyl cyanide molecules (R = C3H5-, 1; R = C2H5-, 2) were synthesized. Thermally induced spin crossover (SCO) in 1 takes place in two poorly resolved stages (T(1)1/2(↓) = T(1)1/2(↑) = 198 K, T(2)1/2(↓) = 170 K, T(2)1/2(↑) = 171 K) whereas in 2 complete and relatively gradual one step SCO (T1/2(↓) = T1/2(↑) = 160 K) occurs. Diversification of the SCO properties of the complexes originates from the ability of coordinated allyl cyanide in 1 to undergo conformational alterations, which is not observed for propionitrile molecules in 2. SCO in 1 is accompanied by a non-monotonic change of the contribution of allyl cyanide conformers which is related to reconstruction of the network of intermolecular contacts established between polymeric layers. The coordination network 1 exhibits extraordinary elasticity and in the second stage SCO, accompanied by conformational changes of allyl cyanide, triggers a crystallographic phase transition which leads to the formation of a superstructure. What is important, the formation of the superstructure is not caused by long range ordering of HS and LS iron(ii) ions. The structural alteration is associated with corrugation of the polymeric skeleton and disappearance of nitrile disorder. Irradiation of a single crystal of 1 at 15 K with laser light (520 nm) allowed producing a novel low temperature HS phase of 1 in which, contrary to the high temperature HS phase, disordering of anion and allyl cyanide molecules is not observed and the corrugated nature of the polymeric layer, characteristic of the LS phase, is preserved.

From the inception of the Boston Medical and Surgical Journal in 1828 until the prominent public demonstration of surgical anesthesia on Ether Day of 1846, ether was often mentioned in the journal. Many of the examples were related to obstetrics. Because molecular structures were not available in the early 1800s, diverse volatile liquids were termed ethers. In addition to sulphuric ether, so-called ethers included cyanide-releasing propionitrile and ethanolic solutions of chloroform and of the potent vasodilator ethyl nitrite. Familiarity with anesthetically unsuitable ethers may have long deterred consideration of inhaled sulphuric ether for analgesia and anesthesia.

This work deals with the phase transfer catalysed cyanide displacement reaction on 1-(4-isobutyl phenyl) ethyl chloride to synthesize 2-(4-isobutyl phenyl) propionitrile, which is an intermediate for the synthesis of ibuprofen analogs, belonging to a class of NSAID (nonsteroidal anti-inflammatory drugs). The reaction was studied using solid–liquid phase transfer catalysis (S-L PTC) with trace quantities of water, forming the so-called omega phase at 90 °C. The rates of reaction and selectivity to the product are enhanced in the S-L(org.)-L (ω) PTC in comparison with S-L PTC, which in turn is superior to L-L PTC; the latter suffers from the disadvantage of side reactions in the aqueous phase. In the current work, the effects of various parameters such as catalyst structure, catalyst loading, substrate loading and temperature were studied on the conversion and rates of reaction of 1-(4-isobutyl phenyl) ethyl chloride with solid sodium cyanide under S-L and S-L(ω)-L PTC at 90 °C with toluene as the organic solvent. Tetrabutylammonium bromide (TBAB) was found to be the best catalyst. The role of omega liquid phase in intensification of the S-L PTC was theoretically and experimentally investigated. The kinetic constants have been determined and the apparent activation energy is found as 4.2 kcal/mol, which suggests that the reaction is quite fast, which is likely to bring in mass transfer effects.

The parameters of the femtosecond vibration—rotation molecular dynamics of liquid acetonitrile CH3CN, trimethylacetonitrile (CH3)3CCN, propionitrile CH3CH2CN, fluoroform CHF3, and chloroform CHCl3 are found by analysing the ultrafast optical Kerr effect. The influence of the molecular structure on the features of rotational (diffusion and libration) motions is studied. It is shown that the distribution of libration frequencies is described by the Maxwell distribution.

A kinetic and mechanistic investigation of the reduction of acrylonitrile, propionitrile and benzonitrile by BH 3 · SMe 2 in CH 2 Cl 2 has been conducted using 11 B NMR spectroscopy. No reduction of propionitrile and benzonitrile was observed at 25 °C, while the reduction of acrylonitrile was monitored to the vinyliminoborane. The reaction exhibited simple second-order kinetics of the form k obs = k 2 ′ [ acrylonitrile ] , with the dissociation of the dimethyl sulfide from borane playing a key role in controlling the reduction process. The activation parameters (Δ S ≠ and Δ H ≠ ) for the reaction of BH 3 · SMe 2 with acrylonitrile were found to be −71 ± 10 J K −1 mol −1 and 58 ± 3 kJ mol −1 , respectively. The B3LYP/6-31G ∗ results for charge distribution and transfer during the reaction show a reversal of charge in the borane–nitrile adduct for the atoms that make up the borane and the nitrogen and carbon atoms in the nitrile. The activation barriers for the reduction of acrylonitrile were found to be 6–8 kJ mol −1 lower than those of hydrogen cyanide, propionitrile and benzonitrile, with its product iminoborane being 30–130 kJ mol −1 more stable than those of the other nitriles.

Rhodococcus sp. NDB 1165, a nitrile-transforming organism was isolated from temperate forest soil of Himalayas. The nitrilase (EC 3.5.5.2) activity of this organism had higher substrate specificity toward aromatic nitriles (benzonitrile, 3-cyanopyridine and 4-cyanopyridine) and unsaturated aliphatic nitrile (acrylonitrile) in comparison to saturated aliphatic nitriles (acetonitrile, propionitrile, butyronitrile and isobutyronitrile) nitrile and arylacetonitrile (phenylacetonitrile and indole-3-acetonitrile). The nitrilase of Rhodococcus sp. NDB 1165 was inducible in nature and propionitrile proved to be an efficient inducer. However, the salts of ferrous and cobalt ions had an inhibitory effect. Under optimized reaction conditions (pH 8.0 and temperature 45°C) the nitrilase activity of this organism was 2.39 ± 0.07 U/mg dry cell mass (dcm). The half-life of this enzyme was 150 min and 40 min at 45°C and 50°C respectively. However, it was quite stable at 40°C and around 58 % activity was retained even after 6 h at this temperature. The V max and K m value of this nitrilase were 1.67 µmol/ml min and 0.1 M respectively using 3-cyanopyridine as substrate. However, the decrease in V max and K m values (0.56 µmol/ml min and 0.02 M, respectively) were ␣observed at >0.05 M 3-cyanopyridine which revealed that this enzyme experienced uncompetitive inhibition at higher substrate concentrations. Under optimized reaction conditions, 1.6 M 3-cyanopyridine was successfully converted in to nicotinic acid using 2.0 mg resting cells (dcm)/ml reaction mixture in 11 h. This is the highest production of nicotinic acid i.e. 8.95 mg/mg resting cells (dcm)/h as compared to nitrilase systems reported hitherto.

Rhodococcus rhodochrous PA-34 exhibited 55 U mg −1 dcw nitrile hydratase (NHase) activity for the transformation of acrylonitrile to acrylamide. The culture conditions of R. rhodochrous PA-34 for the production of NHase and reaction conditions for this NHase mediated conversion of acrylonitrile to acrylamide were optimised. The maximum production of NHase (2.5 U mL −1 culture) was carried out by culturing R. rhodochrous PA-34 in the medium containing (L −1 ) 10.0 g glycerol, 5.0 g peptone, 3.0 g yeast extract, 20 mg CoCl 2 , pH 7.0, 2 mL propionitrile at 30 °C for 36 h in an incubator shaker (160 rpm). The maximum conversion of acrylonitrile to acrylamide was observed in 100 mM potassium phosphate buffer (pH 7.0), at 10 °C, acrylonitrile (8%, w/v, i.e. 1500 mM) using resting cells of this organism corresponding to 1.6 mg dry cell weight (dcw) mL −1 reaction mixture (specific activity 55 U mg −1 dcw) in 1 h. The resting cells of R. rhodochrous PA-34 retained 76% NHase activity even in the presence of 20% (w/v) acrylonitrile. The conversion of acrylonitrile to acrylamide was carried out at 1 L scale and 600 g (8442 mM) of acrylamide was produced in 12 h at 10 °C.

IVCT solvatochromism studies on the meso and rac diastereoisomers of [{Ru(bpy)2}2(μ-bpm)]5+ (bpy = 2,2′-bipyridine; bpm = 2,2′-bipyrimidine) in a homologous series of nitrile solvents revealed that stereochemically directed specific solvent effects in the first solvation shell dominated the outer sphere contribution to the reorganizational energy for intramolecular electron transfer. Further, solvent proportion experiments in acetonitrile/propionitrile mixtures indicated that the magnitude and direction of the specific effect was dependent on the relative abilities of discrete solvent molecules to penetrate the clefts between the planes of the terminal polypyridyl ligands. In particular, the specific effects were dependent on the dimensionality of the clefts, and the number, size, orientation and location of the solvent dipoles within the interior and exterior clefts. IVCT solvatochromism studies on the diastereoisomeric forms of [{Ru(bpy)2}2(μ-dbneil)]5+ and [{Ru(pp)2}2(μ-bpm)]5+ {dbneil = dibenzoeilatin; pp = substituted derivatives of 2,2′-bipyridine and 1,10-phenanthroline} revealed that the subtle and systematic changes in the nature of the clefts by the variation of the bridging ligand, and the judicious positioning of substituents on the terminal ligands, profoundly influenced the magnitude of the reorganizational energy contribution to the electron transfer barrier.

The low temperature adsorption of CO and the room temperature adsorption of propionitrile (PrN), isobutyronitrile (IBN) and pivalonitrile (2,2-dimethyl-propionitrile, PN) have been investigated on NaX (Si/Al atomic ratio = 1.3) and NaY (Si/Al atomic ratio = 2.4) zeolites by FT-IR spectroscopy. The bands of CO adsorbed on NaY have been reassigned. The relevance of Na + ions at S III or S III′ positions also on NaY has been emphasized. Evidence is provided for the formation of complex interactions where nitrile molecules interact with more than one site, likely more than one Na ion, as previously observed on alkali metal containing MOR zeolites. The possible relevance of this interaction is briefly discussed.

Ethyl α-cyano-β-(p-fluorophenyl)-β-(2-furyl)propionate was obtained by the condensation of ethyl α-cyano-β-(2-furyl)acrylate with p-fluorophenylmagnesium bromide. Its deethoxycarbonylation led to β-(p-fluorophenyl)-β-(2-furyl)propionitrile. Reduction of the nitrile with lithium aluminum hydride gave γ-(p-fluorophenyl)-γ-(2-furyl)propylamine. Some transformations of the latter were studied.

Solvothermal reactions of AgNO3, NaN3 with acetonitrile and propionitrile in methanol yield two non-interpenetrated supramolecular networks, [Ag(Mtta)]n (1) and [Ag(Etta)]n (2) (Mtta = 5-methyl tetrazolate, Etta = 5-ethyl tetrazolate), respectively, involving ligand in situ formation by cycloaddition of nitriles and azides. Difference of steric hindrance from substituted groups in tetrazole leads to the diversity of topological networks: 1 possesses 2-D 3-connected (4.82)Ag (4.82)Mtta topological network, whereas complex 2 is a 3-D 3-connected (10,3)-a metal network.

Twelve different derivatives of substituted-{5-[2-(1,2,3,4-tetrahydrocarbazol-9-yl)ethyl]tetrazol-1-yl}alkanones ( 3 – 14 ) were synthesized by reacting 9-[2-(1 H -tetrazol-5-yl)-ethyl]-2,3,4,9-tetrahydro-1 H -carbazole ( 2 ) and the appropriate acid chlorides. 9-[2-(1 H -tetrazol-5-yl) ethyl]-2,3,4,9-tetrahydro-1 H -carbazole ( 2 ) was synthesized by reacting 3-(1,2,3,4-tetrahydrocarbazol-9-yl) propionitrile ( 1 ) with sodium azide and ammonium chloride. The chemical structures were confirmed by means of IR, 1 H-NMR, mass spectra and elemental analysis. The compounds were screened for antinociceptive activity by acetic acid induced writhing method and hot plate method. 1-Phenyl-2-{5-[2-(1,2,3,4-tetrahydrocarbazol-9-yl)ethyl]tetrazol-1-yl}ethanone ( 13 ) was found to be the most active compound of the series.

The transferable potentials for phase equilibria (TraPPE) force fields are extended to amine, nitro, nitrile, and amide functionalities and to pyridine and pyrimidine. In many cases, the same parameters for a functional group are used for both united-atom and explicit-hydrogen representations of alkyl tails. Following the TraPPE philosophy, the nonbonded interaction parameters were fitted to the vapor-liquid coexistence curves for selected one-component systems. Coupled-decoupled configurational-bias Monte Carlo simulations in the Gibbs ensemble were applied to neat (methyl-, dimethyl-, trimethyl-, ethyl-, diethyl-, or triethyl-)amine, nitromethane, nitroethane, nitrobenzene, acetonitrile, propionitrile, acetamide, propanamide, butanamide, pyridine, and pyrimidine. Excellent agreement with experimental results was found, with the mean unsigned errors being less than 1% for both the critical temperature and the normal boiling temperature. Similarly, the liquid densities at low reduced temperatures are reproduced to within 1%, and the deviation for the critical densities is about 4%. Additional simulations were performed for the binary mixtures of methylamine + n-hexane, diethyl ether + acetonitrile, 1-propanol + acetonitrile, and nitroethane + ethanol. With the exception of the methylamine/n-hexane mixture for which the separation factor is substantially overestimated, agreement with experiment for the other three mixtures is very satisfactory.

The effect of synthesis conditions on the formation of the phase composition, dispersity, pore structure, and acid-base properties of alkaline earth oxides, rare earth oxides, and the Mg-M-O (M = Y, La, or Ce) and Y(La)-M-O (M = Ca, Sr, or Ba) binary systems was studied. It was found that the nature of the system was responsible for the character of phase transformations: the Mg-M-O samples were a mixture of either MgO with Y2O3 or MgO with a solid solution based on rare earth oxides (LaMg)2O3 or (CeMg)O2); the Y(La)-M-O samples (M = Ca, Sr, or Ba) contained the M2Y2O5, MY2O4, and MLa2O4 compounds, which differ in chemical stability, in addition to La2O3 and Y2O3 phases. According to XPS data, the M/Mg atomic ratios were much higher than the bulk values; this is indicative of an enrichment of the surface of samples in the second component. An increase in the concentration of M2O3 from 5 to 25 mol % resulted in a decrease in the S sp of the Mg-M-O samples from 220 ± 10 to 110 ± 10 m2/g; the S sp of samples calcined at 750°C was lower by a factor of ∼1.5–2. The S sp of the Y(La)-M-O samples was higher than the S sp of individual La2O3 and Y2O3. The samples were characterized by a biporous texture. The concentrations and strength distributions of surface OH groups, Lewis acid sites, and Lewis base sites depend on the nature and concentration of rare earth elements in the binary samples. The activity of the Mg-M-O samples in the oxidative dehydrogenation reaction of propionitrile correlated with the acid-base surface sites. Among the Ru/Y(La)-M-O catalysts for ammonia synthesis, Ru/Y-Ba-O was the most active; this catalyst provided a higher yield of NH3 at 250–300°C, as compared with catalysts prepared with the use of other supports (Sibunit, KVU-1, and C/MgO).

Synthesis, Characterization, and Structure of the Donor-stabilized Monomeric [PS3]− Anion (Monometatrithiophosphate) The reaction between H2S and some σ4λ5-derivatives of the monometa-dithioxaphosphoric acid, [PyPS2X] (Py = pyridine, X = Cl, NR2), at low temperature in propionitrile as a solvent leads to the formation of the corresponding ammonium salts with the new anion [PyPS3]− (1). The single crystal structure determinations of three compounds 1a-1c bearing the new title anion 1 reveal the existence of considerably short distances between the nitrogen of the cation and the sulphur atoms of the anion connected by a cationic proton in all cases. These hydrogen bond contacts fall below the sum of van der Waals radii of nitrogen and sulphur and are crucial for the stabilization of 1 in the crystals which is an electronical support in nature. If acidic hydrogen atoms are not present in the cations of the salts as in the case of tetraphenylarsonium as a counter cation a stabilisation of the new anion 1 does not occur. In this case, even from pyridine solutions, only the salt with the well known dimeric anion [PS3]22− crystallizes.

A versatile nitrile-degrading bacterium was isolated by enrichment culture from the soil of a forest near Manali, Himachal Pradesh, India, and was identified as Nocardia globerula. This organism contains 3 enzymes with nitrile-degrading activity: nitrilase, nitrile hydratase, and amidase. Nocardia globerula NHB-2 cells grown on nutrient broth supplemented with 1% glucose and 0.1% yeast extract exhibited nitrile hydratase–amidase activity specific for saturated aliphatic nitriles or amide, while addition of acetonitrile in nutrient broth yielded cells with nitrile hydratase–amidase that in addition to saturated aliphatic nitriles–amide also hydrolyzed aromatic amide. Nocardia globerula NHB-2 cultivated on nutrient broth containing propionitrile exhibited nitrilase activity that hydrolyzed aromatic nitrile and unsaturated aliphatic nitrile. The versatility of this organism in the hydrolysis of various nitriles and amides makes it a potential bioresource for use in organic synthesis.Key words: Nocardia globerula NHB-2, nitrilase, nitrile hydratase, amidase, nitrile–amide degradation.

cis-Azobenzene was generated from trans-azobenzene directly inside an electrochemical cell by irradiation with light from a mercury lamp. The formation of the cis-isomer was proved by recording the UV–VIS absorption spectra of a trans-azobenzene solution in acetonitrile after different periods of irradiation. The reduction half-wave potentials of cis-azobenzene have been determined by photomodulated voltammetry in eight solvents (acetonitrile, propionitrile, butyronitrile, benzonitrile, dimethylformamide, dimethylsulfoxide, propylene carbonate, and tetramethylurea), ranging from −1 to −2.2 V vs. SCE. A six step reaction mechanism is proposed. From the large variety of existing Linear Solvation Energy Relationships, the obtained half wave potentials fit well to the π*-scale and to the Unified Solvation Model.

The reaction of N -fluoropyridinium triflate with isonitriles in acetonitrile and propionitrile in the presence of NaBH(OAc) 3 led to the formation of the corresponding imidazo[1,2- a ]pyridines in 44–73% yields. The proposed reaction mechanism involves the intermediate formation of a highly reactive carbene species and apparent reduction of the pyridinium intermediate with NaBH(OAc) 3 to yield the targeted heterocycles.

Excess molar volumes, VmE, have been obtained as a function of composition for ternary-pseudobinary mixtures of [(benzene + cyclohexane or methylcyclohexane) + (propionitrile + cyclohexane or methylcyclohexane)] from the densities measured by means of a vibrating-tube densimeter at atmospheric pressure and a temperature of 298.15 K. The values of VmE have been correlated using the Redlich–Kister equation to estimate the coefficients and standard errors. The experimental and calculated quantities are used to discuss the mixing behavior of the components. The results show that the third component, cyclohexane or methylcyclohexane, has a significant effect on the interaction between benzene and propionitrile.

N-N cleavage of the dialkylhydrazido complex [W(dppe)2(NNC5H10)] (B(W)) upon treatment with acid, leading to the nitrido/imido complex and piperidine, is investigated experimentally and theoretically. In acetonitrile and at room temperature, B(W) reacts orders of magnitude more rapidly with HNEt3BPh4 than its Mo analogue, [Mo(dppe)2(NNC5H10)] (B(Mo)). A stopped-flow experiment performed for the reaction of B(W) with HNEt3BPh4 in propionitrile at -70 degrees C indicates that protonation of B(W) is completed within the dead time of the stopped-flow apparatus, leading to the primary protonated intermediate B(W)H+. Propionitrile coordination to this species proceeds with a rate constant k(obs(1)) of 1.5 +/- 0.4 s(-1), generating intermediate RCN-B(W)H+ (R = Et) that rapidly adds a further proton at Nbeta and then mediates N-N bond splitting in a slower reaction (k(obs(2)) = 0.35 +/- 0.08 s(-1), 6 equiv of acid). k(obs(1)) and k(obs(2)) are found to be independent of the acid concentration. The experimentally observed reactivities of B(Mo) or B(W) with acids in nitrile solvents are reproduced by DFT calculations. In particular, geometry optimization of models of solvent-coordinated, Nbeta-protonated intermediates is found to lead spontaneously to separation into the nitrido/imido complexes and piperidine/piperidinium, corresponding to activationless heterolytic N-N bond cleavage processes. Moreover, DFT indicates a spontaneous cleavage of nonsolvated B(W) protonated at Nbeta. In the second part of this article, a theoretical analysis of the N-N cleavage reaction in the Mo(III) triamidoamine complex [HIPTN3N]Mo(N2) is presented (HIPTN3N = hexaisopropylterphenyltriamidoamine). To this end, DFT calculations of the Mo(III)N2)triamidoamine complex and its protonated and reduced derivatives are performed. Calculated structural and spectroscopic parameters are compared to available experimental data. N-N cleavage most likely proceeds by one-electron reduction of the Mo(V) hydrazidium intermediate [HIPTN3N]Mo(NNH3)+, which is predicted to have an extremely elongated N-N bond. From an electronic-structure point of view, this reaction is analogous to that of Mo/W hydrazidium complexes with diphos coligands. The general implications of these results with respect to synthetic N2 fixation are discussed.

We have developed a simple and sensitive method for determining acetonitrile and propionitrile in human whole blood using capillary gas chromatography (GC) with cryogenic oven trapping. After heating 0.5 ml of a whole blood sample containing both nitriles and 0.5 ml of distilled water in a 7-ml vial at 75℃ for 15 min, 5 ml of the headspace vapor was drawn into a 10-ml syringe and injected to GC with a flame thermionic detector. A sharp peak was obtained for acetonitrile at -10℃ of the initial oven temperature. The extraction efficiencies for acetonitrile and propionitrile were 0.27 and 0.40%, respectively. For quantitation of acetonitrile, propionitrile was used as internal standard, and vise versa. The calibration curves for both compounds gave good linearity in the range of 0.2-6 μg/ml whole blood. The detection limits (signal to noise ratio = 3) were 0.05μg/ml for acetonitrile and 0.01μg/ml for propionitrile. The coefficients of intra-day variations were 1.0% at 0.4μg/ml and 1.7% at 2μg/ml for acetonitrile; 7.1% at 0.4μg/m1 and 1.0 % at 2μg/ml for propionitrile. This method can be applicable for determining these nitriles in whole blood samples in acute and chronic intoxication cases.

Carbonization of the surface of alumina-based catalysts has been studied with respect to the composition of the catalysts and conditions of the propionitrile ammonolysis. It was shown that the surface concentration of carbon increases with the increase in temperature and with time of the reaction and depends on the catalysts nature in the order: Al-Zr(5)-O < Al-Zr(40)-O < Al-O < Al-Mg-O. The surface concentration of the Bronsted acidic sites follows the same sequence.

This study extends the use of two lathyrogens, ss-aminopropionitrile (BAPN) and D-penicillamine (DPA) from daily systemic or local-topical administration to long-time acting agents. This was achieved by converting the hydrophilic drugs into lipophilic derivatives. The synthesis of functional derivatives of DPA consisted in esterification with methyl-, hexyl-, or benzyl alcohols in the presence of thionylchloride. The esters formed were hydrochlorides, acidic and soluble in water. During neutralization in vitro or in vivo by tissue fluid, an oily substance is formed that elutes from a hydrogel polymer at a much slower rate than hydroplilic DPA itself. The degree of lipophilicity, measured as a partition coefficient between octanol/water, was highest for hexyl ester and lowest for methyl ester DPA. A single injection of either DPA hexyl ester HCl or 3-hexyl(amino) propionitrile into the full thickness skin incision wound in rats significantly lowered the breaking strength of the wound 12 days after injection, indicating the interference with collagen cross-linking. Both agents injected into the breast adenocarcinoma in Fisher rats significantly inhibited tumor growth without any signs of local or systemic toxicity. We conclude that these lipophilic lathyrogens with prolonged effectiveness are suitable in the treatment of pathologies, consisting of excessively cross-linked or deposited collagen (fibrotic adhesions, strictures, stenosis, and scar contractures) and in the treatment of single, solitary tumors, malignant and benign.

Synthesis of (R)-2-trimethylsilyl-2-hydroxyl-propionitrile via asymmetric transcyanation of acetyltrimethylsilane with acetone cyanohydrin in an aqueous/organic biphasic system catalyzed by (R)-hydroxynitrile lyase from Prunus japonica seed meal was successfully carried out for the first time. The optimal volume ratio of aqueous to organic phase, buffer pH value and reaction temperature were 15% (v/v), 5.0 and 30°C, respectively, under which both substrate conversion and product enantiomeric excess (ee) were 99%. Silicon atom in the substrate showed great effect on the reaction. Acetyltrimethylsilane was a much better substrate for (R)-hydroxynitrile lyase from Prunus japonica than its carbon analogue.

A compound of 9,9-dipropionitrilefluorene (C19H16N2,Mr=272.34) was synthesized via nucleophilic addition reaction under microwave irradiation (500 w) within short reaction time (8 min), giving high yield of product (87%). Its structure was determined IR,1H NMR, MS, elemental analysis and X-ray diffraction. The crystal belongs to monoclinic, space group P2(1)/c witha= 21.8358(16),b= 8.9457(7),c= 15.9895(12) Å, β = 105.078(2)o, V= 3015.8(4) Å3,Z=8,Dc= 1.200 g/cm3,μ=0.071 mm-1,F(000)=1152,R=0.0629 andwR= 0.0881 for 3155 observed reflection with I>2σ (I). X-ray analysis reveals that the three fused rings of the fluorene system are almost coplanar and the two propionitrile groups are completely perpendicular to the fused-ring system, the molecular is symmetrical.

A series of 2‐cyano‐3‐aryl‐3‐(3,4‐dihydro‐1(2H)‐naphthalene‐one‐2‐yl) propionitrile derivatives and 2‐aminopyran derivatives were synthesized by the KF‐Al2O3‐catalyzed reaction of malononitrile with 2‐arylmethylidene‐3,4‐dihydro‐1(2H)‐naphthalenone, 2,6‐biarylmethylidene cyclohexanone, or 2,5‐biarylmethylidene cyclopenanone in DMF at room temperature. The structure of the later was confirmed by x‐ray analysis.

The interaction of triethoxysilane (TES) with H-ferrierite (H-FER) and its effects on acidity have been investigated by infrared spectroscopy. TES adsorbs only on the external surface of H-FER and allows the almost complete disappearance of the external silanol groups. New SiH groups are formed which appear to be inactive in acid-base interactions. The adsorption of propionitrile, which diffuses into the zeolitic channels, provides evidence for the lack of substantial perturbation of the strongly acidic internal bridging OH groups. On the contrary, the adsorption of the hindered basic probe molecule o-toluonitrile, which cannot penetrate the FER channels, shows that not only terminal silanols but also Al3+ Lewis acid sites present on the external surface of H-FER almost totally disappear after TES treatment. Treatment with TES seems to allow virtually the total deactivation of the H-FER external surface.

Considering the extensive applications of oleochemicals as industrial products, a series of novel 9-[substituted amido]-16-ol-hexadecanoic acids have been synthesized by the reaction of different nitriles with 16-hydroxyhexadec-cis-9-enoic acid. The specific nitriles, including acetonitrile, propionitrile, β-methoxypropionitrile, β-ethoxypropionitrile, β-(2-ethoxy)ethoxypropionitrile, β-butoxypropionitrile, β-amyloxypropionitrile, β-isoamyloxypropionitrile, ethylcyanoacetate, o-carboxyphenylacetonitrile, benzonitrile, and benzyl cyanide, were added to the double bond of 16-hydroxyhexadec-cis-9-enoic acid in the presence of concentrated sulfuric acid followed by hydrolysis. The mechanism of acid-catalyzed addition of nitriles to 16-hydroxyhexadec-cis-9-enoic acid has been confirmed by its amido−imidol tautomerization. Thus, the addition of nitriles at carbon-9, instead of carbon-10, of 16-hydroxyhexadec-cis-9-enoic acid has been confirmed by mass spectral fragmentation of McLafferty rearrangement due to th...

N-Lauroyl-β-amino propionitrile is an intermediate for synthesis of sodium N-lauroyl-β-alanine, an antimicrobial surfactant. We provide a novel process for enzymatic synthesis of N-lauroyl-β-amino propionitrile, using a cascade connection of an enzyme packed bed reactor (EPBR) with a crystallization separator for on-line separation. The substrate solution was fed to the reactor inlet. High-purity crystal product was obtained from the separator outlet with a yield of 91.7% under the optimum conditions. The immobilized lipase can be utilized repeatedly. The solvent and unreacted substrates were recovered and reused on-line.

Reaction of 5,5-dimethyldipyrromethane (1) with electron-deficient aryl aldehydes in the presence of BF(3)-Et(2)O and NH(4)Cl in propionitrile constitutes efficient, easy access to unprecedented, functional porphomonomethenes together with the expected porphodimethenes (calix[4]phyrins). Alternatively, when the reaction was carried out in CH(2)Cl(2) in the presence of an acid and Florisil, the expected bis-arylcalix[4]phyrin was isolated in 41% yield, while no scrambled macrocycle was detected. After reduction of the nitro function, porphomonomethene 9 was efficiently condensed with the binaphthyl diacyl chloride (10) leading to the first chiral calix[4]phyrin dimer (11) that exhibits a moderate enantiorecognition toward the enantiomers of malic acid.

The excess molar volumes VEm for ternary pseudo-binary mixtures of [(benzene+chloroform or carbon tetrachloride)+(propionitrile+chloroform or carbon tetrachloride)] have been determined over the full composition range, by measuring the densities with a vibrating-tube densimeter at 298.15 K and atmospheric pressure. The experimental and calculated quantities are compared to those for the binary mixture (benzene+propionitrile), and the mixing behavior of the components is discussed. The results show that adding the third component, chloroform or carbon tetrachloride, to the binary mixture has a small effect on the interaction between benzene and propionitrile.

The scope of TMSOTf-promoted glycosidation of 2-azido-2-deoxyglycopyranosyl diphenyl phosphates is investigated. The 3,4,6-tri- O -benzyl-protected glucosyl and galactosyl donors and the 4,6- O -benzylidene-protected galactosyl donor each react with a range of acceptor alcohols in the presence of a stoichiometric amount of TMSOTf in propionitrile at −78 °C to afford 1,2- trans -β-linked disaccharides in high yields with α : β ratios ranging from 9:91 to 1:>99, regardless of the anomeric composition of the donor used. The use of propionitrile as a solvent at −78 °C has proven to be among the best choice for the highest levels of β-selectivity reported to date for this type of glycosidation. A plausible reaction mechanism, which features a large equilibrium preference for α-glycosyl-nitrilium ions over β-nitrilium ions, is proposed based on byproducts formed through their intermediacy and accounts for the observed excellent β-selectivities.

The CH bond dissociation energies were calculated spectroscopically for acetonitrile, propionitrile, isobutyronitrile, and trimethylacetonitrile from the fundamental absorption bands in the anharmonic approximation using the variational technique with the Morse-harmonic basis set. A similar calculation was carried out for various associates of acetonitrile. Due to this, CH bond dissociation energies were determined for the liquid state of acetonitrile.

Propagation of PAMAM (polyamidoamine) dendrons on solid spherical silica gel was achieved by a series of alternate Michael addition and amidation reactions. The reaction kinetics studies were investigated quantitatively. A newly developed method of immobilizing inert 3-(triethoxysilyl) propionitrile (TESPN) on silica before construction of PAMAM dendrons provided an internal standard to normalize drift IR spectra for kinetics studies. A reaction kinetic model was proposed on the basis of IR spectra and TGA measurements. The simulated results match with the experimental data and confirm consistency with the proposed kinetic model that a “cross-linking” reaction occurred in amidation generating structural defects, and steric hindrance existed during the Michael addition reaction. Furthermore, we found that the TESPN immobilized on silica acted as a “spacer” to reduce the initial density of amino groups on silica and improved the synthesis efficiency remarkably. The reaction kinetics study in this paper is i...

Trifluoromethanesulfonate and tetrafluoroborate salts of the previously in situ-generated synthetic precursor [Tp*W(NCMe)(CO) 3 ] + and a propionitrile analogue, [Tp*W(NCEt)(CO) 3 ](CF 3 SO 3 ), have been isolated and fully characterized. The complex cations exhibit a carbonyl-capped octahedral structure with C s symmetry and undergo slow nitrile ligand exchange.

The relative effects of a series of eight saturated (acetonitrile, propionitrile and n-butyronitrile) and unsaturated (acrylonitrile, allylnitrile, methacrylonitrile, cis-2-pentenenitrile, and 2-chloroacrylonitrile) aliphatic nitriles were evaluated using an in vitro test for embryotoxicity, the rat limb bud micromass assay. The concentrations that produced 50% inhibition (IC50) of viability and differentiation of the cultured embryonic cells were of the same order of magnitude, whatever tested compound. The IC50 values spread over a wide concentration range from 7–11 μM to 150 mM. Acetonitrile and 2-chloroacrylonitrile were the least and most potent compounds, respectively. The tested chemicals were evaluated using different criteria proposed to identify teratogens in the micromass system, based on either active concentrations or specific inhibition of cell differentiation. A few incorrect classifications were obtained with both nonteratogens and teratogens, when comparing the activity in limb bud cell cultures with the data available on their in vivo teratogenic potential in rats. The concordance between the in vitro and in vivo responses of this set of nitriles was judged insufficient to consider the micromass assay valuable for predicting the in vivo teratogenic outcome of this class of compounds.

The liquid structure of acetonitrile (AN), propionitrile (PN), acrylonitrile (ACN), and benzonitrile (BN) was investigated by the transmission mode X-ray diffraction method with a newly developed CCD detector at room temperature and one atmospheric pressure. The nitriles were shielded in a thin wall glass tube. The reduced intensities, si(s), extracted from the measured intensities were compared with those obtained by the X-ray diffraction measurements with the θ–θ type reflection mode for benzonitrile and N,N-dimethylformamide (DMF) as the reference. In all the nitriles it was found that molecules are arrayed in the zigzag form as found in previous studies for AN. The non-bonding N···C (nitrile carbon) distance between the anti-parallel adjacent molecules was 340 pm for all nitriles. The intermolecular C···C distance between next neighbour molecules was 420 pm for CH2···CH2 in AN, 430 pm for CH3···CH3 in PN, 425 pm for CH···CH in ACN, and 390 pm for C6H5···C6H5 in BN. The short C6H5···C6H5 distance was explained in terms of the π–π stacking interactions of the aromatic rings. DMF molecules interact each other through dipole–dipole interactions, and the O···C distance of 320 pm at the O···H–CO– interaction through the formyl proton may partly contribute to the intermolecular interactions. The distance between parallel DMF molecules in a plane was estimated to be 743 pm. The diffraction data were well explained in terms of a weak layered structure of DMF, and the layers were separated by about 365 pm.

The hydrogen transfer reaction of antioxidative polyphenol with reactive oxygen species has proved to be the main mechanism for radical scavenging. The planar catechin (P1H(2)), in which the catechol and chroman structure in (+)-catechin (1H(2)) are constrained to be planar, undergoes efficient hydrogen atom transfer toward galvinoxyol radical, showing an enhanced protective effect against the oxidative DNA damage induced by the Fenton reaction. The present studies were undertaken to further characterize the radical scavenging ability of P1H(2) in the reaction with cumylperoxyl radical, which is a model radical of lipid peroxyl radical for lipid peroxidation. The kinetics of hydrogen transfer from catechins to cumylperoxyl radical has been examined in propionitrile at low temperature with use of ESR, showing that the rate of hydrogen transfer from P1H(2) is significantly faster than that from 1H(2). The rate was also accelerated by the presence of Sc(OSO(2)CF(3))(3). Such an acceleration effect of metal ion indicates that the hydrogen transfer reaction proceeds via metal ion-promoted electron transfer from P1H(2) to oxyl radical followed by proton transfer rather than via a one-step hydrogen atom transfer. The electrochemical ease of P1H(2) for the one-electron oxidation investigated by second-harmonic alternating current voltammetry strongly supports the two step mechanism for hydrogen transfer, resulting in the enhanced radical scavenging ability.

Air- and moisture-sensitive Fe(NO)3(η1-PF6) (1) may be conveniently prepared by treating Fe(NO)3Cl with 1 equiv of [Ag][PF6] in CH2Cl2 or by reacting [NO][PF6] with excess iron filings in MeNO2. Complex 1 is thermally sensitive both as a solid and in solutions, and is best handled below −20 °C. To isolate 1 reproducibly from MeNO2 solutions it is necessary to remove all traces of propionitrile, which often occurs as an impurity in MeNO2, because it reacts with Lewis-acidic 1 to form [Fe(NO)3(EtCN)][PF6] (2). If trace H2O is present during the synthesis of 1, some of the PF6- is converted to PO2F2-, which is sufficiently Lewis basic that it captures two Fe(NO)3+ fragments and forms [(ON)3Fe(μ-PO2F2)Fe(NO)3][PF6] (3). Finally, Fe(NO)3(η1-BF4) (4) can be obtained as a green microcrystalline powder by employing the same synthetic methodologies used to prepare 1. The new complexes 1−4 have been characterized by conventional spectroscopic methods, and the solid-state molecular structures of 2, 3, and 4 and thei...

KF loaded on alumina heated under vacuum at 673 K (KF/Al 2 O 3 ) quantitatively gave benzyloxytriethylsilane by addition of triethylsilane to benzaldehyde at 303 K in N , N -dimethylformamide (DMF). KF/Al 2 O 3 also catalyzed the reaction of trimethylsilylacetonitrile with benzaldehyde to give 3-phenyl-3-(trimethylsilyloxy)propionitrile with a 81% yield at 313 K in tetrahydrofuran (THF) while it gave cinnamonitrile with a 61% yield in DMF, along with trimethylsilanol.

Rates of hydrogen-transfer reactions from a series of para-substituted N,N-dimethylanilines to cumylperoxyl radical and oxygen-transfer reactions from cumylperoxyl radical to a series of sulfides and phosphines have been determined in propionitrile (EtCN) and pentane at low temperatures by use of ESR. The observed rate constants exhibit first-order and second-order dependence with respect to concentrations of N,N-dimethylanilines. This indicates that the hydrogen- and oxygen-transfer reactions proceed via 1:1 charge-transfer (CT) complexes formed between the substrates and cumylperoxyl radical. The primary kinetic isotope effects are determined by comparing the rates of N,N-dimethylanilines and the corresponding N,N-bis(trideuteriomethyl)anilines. The isotope effect profiles are quite different from those reported for the P-450 model oxidation of the same series of substrates. Rates of electron-transfer reactions from ferrocene derivatives to cumylperoxyl radical have also been determined by use of ESR. The catalytic effects of Sc(OTf)(3) (OTf = triflate) on the electron-transfer reactions are compared with those of Sc(OTf)(3) on the hydrogen- and oxygen-transfer reactions. Such comparison provides strong evidence that the hydrogen- and oxygen- transfer reactions of cumylperoxyl radical proceed via a one-step hydrogen atom and oxygen atom transfer rather than via an electron transfer from substrates to cumylperoxyl radical.

Solubilities of C.I. Disperse Orange 25 (3-[N-ethyl-4-(4-nitrophenylazo)phenylamino]propionitrile) and C.I. Disperse Blue 354 ([2-[[4-(dihexylamino)-2-methylphenyl]methylene]-1,1-dioxidobenzo[b]thien-3(2H)-ylidene]propanedinitrile) in supercritical carbon dioxide were measured by a flow-type apparatus. The solubility measurements were carried out at the temperature range from (323.15 to 383.15) K and the pressures from (10.0 to 30.0) MPa. The solubility of the dyes was examined in terms of pressure, temperature, and the density of supercritical carbon dioxide. An empirical equation was used to correlate the experimental solubilities of the dyes in terms of the density of carbon dioxide. Furthermore, the experimental data were represented successfully using a modified form of the PRSV (Peng−Robinson−Stryjek−Vera) EOS (equation of state), where vapor pressures and molar volumes of the dyes were calculated simultaneously.

Ultrasonic speed u and dilatometric measurements of excess volume VE have been carried out for mixtures of pyrrolidin-2-one (PY) with acetonitrile (ACN), propionitrile (PN), butyronitrile (BN), valeronitrile (VN), acrylonitrile (ACRN) and benzonitrile (BEN) at 303.15 K over the entire composition range. All the mixtures exhibit negative excess volumes, the curves being nearly symmetrical. The magnitude of the minimum increases steadily with decreasing molar size of the nitrile. The molar isentropic compressibility KS has been computed by combining ultrasonic velocity and excess volume data. Excess molar isentropic compressibility KSE is also negative in all the mixtures over the whole composition range. The data are interpreted in terms of moderate interactions of all kinds decreasing in importance with increasing nitrile carbon chain length. Partial and apparent molar quantities have been estimated to gain insight into interactions. Prigogine–Flory–Patterson theory has been utilised for the quantitative estimation of different contributions viz. interactional, free volume and P* effect to excess volume.

The kinetic and thermodynamic behavior of O2-binding to Cu(I) complexes can provide fundamental understanding of copper(I)/dioxygen chemistry, which is of interest in chemical and biological systems. Here we report stopped-flow kinetic investigations of the oxygenation reactions of a series of tetradentate copper(I) complexes [(LR)CuI(MeCN)]+ (1R, R = H, Me, tBu, MeO, Me2N) in propionitrile (EtCN), tetrahydrofuran (THF), and acetone. The syntheses of 4-pyridyl substituted tris(2-pyridylmethyl)amine ligands (LR) and copper(I) complexes are detailed. Variations of ligand electronic properties are manifested in the electrochemistry of 1R and ν(CO) of [(LR)CuI−CO]+ complexes. The kinetic studies in EtCN and THF show that the O2-reactions of 1R follow the reaction mechanism established for oxygenation of 1H in EtCN (J. Am. Chem. Soc. 1993, 115, 9506), involving reversible formation (k1/k-1) of [(LR)CuII(O2-)]+ (2R), which further reacts (k2/k-2) with 1R to form the 2:1 Cu2O2 complex [{(LR)CuII}2(O22-)]2+ (3R)....

The relative viscosities were measured for LiI, NaI, KI, RbI, Bu4NBPh4, and Bu4NI in a wide range of mixtures of propionitrile and acetonitrile at 25°C to obtain Jones–Dole Bcoefficients. The Bcoefficients of these electrolytes were large and positive. The values of ionic Bcoefficients allow us to assess the behavior of ions in the solvent mixtures.