Reaction Of Nitriles Research Articles

Functionalization of polyacrylonitrile with tetrazole groups for ultrafiltration membranes

A series of tetrazole-functionalized polyacrylonitrile (TZ-PAN) copolymers were synthesized via a post-modification cycloaddition reaction of nitriles with azide for ultrafiltration (UF) membrane application.

Clean synthesis of primary to tertiary carboxamides by CsOH-catalyzed aminolysis of nitriles in water

Using CsOH as the only catalyst and utilizing its “cesium effect”, a clean synthesis of a wide range of primary, secondary, and tertiary carboxamides was achieved by aminolysis reactions of nitriles with ammonia, primary, or secondary amines in water.

Cu-MCM-41 nanoparticles: An efficient catalyst for the synthesis of 5-substituted 1H-tetrazoles via [3+2] cycloaddition reaction of nitriles and sodium azide

[3 + 2] cycloaddition reaction of various types of nitriles and sodium azide (NaN 3) were studied in the presence of nano-sized Cu-MCM-41 as an efficient recoverable heterogeneous catalyst. Nano-sized Cu-MCM-41 mesoporous molecular sieves with various Si/Cu molar ratios were synthesized by direct insertion of metal ions at room temperature. The textural properties of the materials have been studied by means of XRD, FTIR, SEM and TEM techniques. Catalytic behavior of Cu-MCM-41 was also investigated by pyridine absorption and potentiometric titration. The reactions data verified characterization results and show that Cu-MCM-41 with Si/Cu molar ratio of 20 has considerably better catalytic activity compared to the other molar ratios. To investigate reusability, the catalyst was recovered by simple filtration and reused for several cycles with consistent activity. Nano-sized Cu-MCM-41 mesoporous molecular sieves with various Si/Cu molar ratios were synthesized by direct insertion of metal ions at room temperature. [3+2] cycloaddition reaction of various types of nitriles and sodium azide (NaN3) were studied in the presence of nano-sized Cu-MCM-41 as an efficient recoverable heterogeneous catalyst.

ChemInform Abstract: Application of a Functionalized Mesoporous Silica Catalyst to the Synthesis of Tetrazoles.

AbstractA new strategy for the formation of a wide range of substituted tetrazoles (II) by using modified MCM‐41 via the [3 + 2] cycloaddition reaction of nitriles and sodium azide is presented.

Uncovering the Role of Metal Catalysis in Tetrazole Formation by an In Situ Cycloaddition Reaction: An Experimental Approach

AbstractUsing an experimental approach, the role of metal catalysis has been investigated in the in situ cycloaddition reaction of nitrile with azide to form tetrazoles. It has been shown that metal catalysis serves to activate the cyano group in the nitrile reagent by a coordinative interaction.

Uncovering the Role of Metal Catalysis in Tetrazole Formation by an In Situ Cycloaddition Reaction: An Experimental Approach.

Using an experimental approach, the role of metal catalysis has been investigated in the in situ cycloaddition reaction of nitrile with azide to form tetrazoles. It has been shown that metal catalysis serves to activate the cyano group in the nitrile reagent by a coordinative interaction.

One-Pot Synthesis of N-Monosubstituted Ureas from Nitriles via Tiemann Rearrangement

Amidoximes, obtained from the reaction of nitriles with hydroxylamine, underwent Tiemann rearrangement in the presence of benzenesulfonyl chlorides (TsCl or <i>o</i>-NsCl) to form the N-substituted cyanamides. Subsequently, acidic hydrolysis of the cyanamides afforded the corresponding N-monosubstituted ureas. The synthesis of N-monosubstituted ureas from nitriles was accomplished by three steps in one pot, which provides a direct access to versatile N-monosubstituted urea derivatives from a wide variety of nitriles.

An Aluminum Hydride That Functions like a Transition-Metal Catalyst.

The reaction of [LAlH2 ] (L=HC(CMeNAr)2 , Ar=2,6-iPr2 C6 H3 ) with MeOTf (Tf=SO2 CF3 ) resulted in the formation of [LAlH(OTf)] (1) in high yield. The triflate substituent in 1 increases the positive charge at the aluminum center, which implies that 1 has a strong Lewis acidic character. The excellent catalytic activity of 1 for the hydroboration of organic compounds with carbonyl groups was investigated. Furthermore, it was shown that 1 effectively initiates the addition reaction of trimethylsilyl cyanide (TMSCN) to both aldehydes and ketones. Quantum mechanical calculations were carried out to explore the reaction mechanism.

Factors affecting reactions of trialkylcyanoborates with imidoyl chlorides/trifluoroacetic anhydride

Methods for generating tert-alkyl organoboron species are in high demand as they are invaluable intermediates for the synthesis of quaternary carbon centres. Herein we report investigations into generation of tert-alkyl organoboron species using imidoyl chlorides as reagents in the organoboron cyanidation reaction. Although alkenyl side-products predominate in particularly hindered cases, tert-alkyl organoboron species can be successfully generated for less hindered examples.

Efficient Synthesis of 5-Substituted 1H-Tetrazoles Catalysed by Silver(I) Bis(trifluoromethanesulfoyl)Nimide

An efficient method is developed for the synthesis of 5-substituted 1H-tetrazoles through the [3 + 2] cycloaddition reaction of nitriles with sodium azide using silver(I) bis(trifluoromethanesulfonyl)imide (AgNTf2) as a catalyst. This procedure provides mild reaction conditions, short reaction times and high yields.

Theoretical description for the Rh(I)-catalyzed borylation mechanism of a typical aryl cyanide

A recent experimental study by Tobisu et al. (J. Am. Chem. Soc. 2012, 134, 115–118.) reported a new type of catalytic borylation reactions, the Rh-catalytic reaction of aryl cyanides with diboron to afford arylboronic acids. To better understand the borylation mechanism at the molecular level, this work provides a theoretical description for the elementary steps of the reaction of a typical aryl cyanide with diboron in the presence of a rhodium catalyst [RhCl(cod)]2 with the aid of DFT calculations. It is found that i) the catalytically active species is the Rh–B complex rather than the Rh–Cl one, ii) the Rh–Ar intermediate is formed through the iminoacyl species rather than the iminylrhodium species previously proposed by Tobisu et al., and iii) the structures of iminoacyl and boryl isocyanide species are also disagreement with those experimental studied by Tobisu et al. Calculated results show a clear mechanistic picture of the catalytic borylation reaction of the aryl cyanide.

Rapid and Economical Colorimetric Detection of Cyanide in Blood Using Vitamin B12

This work was aimed at the development and validation of an economical colorimetric method for detection of cyanide in whole blood. The method was based on the reaction of hydrogen cyanide with vitamin B12. The hydrogen cyanide is released on acidification of the blood sample. The vitamin B12 was loaded on a strip of a commonly used filter paper by impregnating the strip in a 1.0% (w/v) solution of vitamin B12 under alkaline conditions. The limit of detection of this method was found to be 1.0 mg L−1 which is lower than the reported lethal blood concentration of cyanide (2.5 mg L−1). The method was free from interferences from the common gases including ammonia, carbon dioxide, arsine, phosphine and carbon monoxide, thiocyanate, organophosphate pesticides and nitrile-containing pesticides. This method was successfully employed for detection of cyanide in several cases reported to the forensic toxicology.

ChemInform Abstract: Zinc‐Mediated One‐Pot Tandem Reaction of Nitriles with Propargyl Bromides: An Access to 3‐Alkynylpyridines.

A one-pot procedure for the synthesis of 3-alkynylpyridines via a zinc-mediated tandem reaction of nitriles with propargyl bromides under extremely mild reaction conditions has been developed. This reaction exhibits high efficiency, broad substrate scope, and good functional group tolerance. In addition, the 3-alkynylpyridines obtained herein were found to be versatile and convenient intermediates for the preparation of fused-heterocyclic compounds with potential biological and material interests.

Cyanohydrin reactions enhance glycolytic oscillations in yeast

Synchronous metabolic oscillations can be induced in yeast by addition of glucose and removal of extracellular acetaldehyde (ACAx). Compared to other means of ACAx removal, cyanide robustly induces oscillations, indicating additional cyanide reactions besides ACA to lactonitrile conversion. Here, 13C NMR is used to confirm our previous hypothesis, that cyanide directly affects glycolytic fluxes through reaction with carbonyl-containing compounds. Intracellularly, at least 3 cyanohydrins were identified. Extracellularly, all signals could be identified and lactonitrile was found to account for ~66% of total cyanide removal. Simulations of our updated computational model show that intracellular cyanide reactions increase the amplitude of oscillations and that cyanide addition lowers [ACA] instantaneously. We conclude that cyanide provides the following means of inducing global oscillations: a) by reducing [ACAx] relative to oscillation amplitude, b) by targeting multiple intracellular carbonyl compounds during fermentation, and c) by acting as a phase resetting stimulus.

Effect of pH on the self-assembly of three Cd(II) coordination compounds containing 5-(4-pyridyl)tetrazole: syntheses, structures, and properties

Hydrothermal reactions of CdSO4, 4-cyanopyridine, and sodium azide yield three metal coordination compounds via controlling the pH, [Cd2(4-ptz)(SO4)(OH)(H2O)2](H2O) (1) [Cd2(4-ptz)(SO4)(OH)(H2O)]n (2), and known [Cd2(4-ptz)2(H2O)4](H2O)2 (3) (4-ptz = 5-(4-pyridyl)tetrazole). The in situ [2 + 3] cycloaddition reaction of nitrile and azide in the presence of Cd(II) produces the multidentate 4-ptz in these compounds. X-ray diffraction results indicate that metal centers in 1 are linked by 4-ptz–, , and OH− in their respective μ5-, μ2-, μ3-bridging modes, forming a 3-D coordination polymer. For 2, although the same raw materials are used, the component anions are linked to Cd(II) centers in completely different ways, i.e. for 4-ptz− in μ3−, in μ5-, and OH− in μ3-bridging modes, forming another 3-D coordination network. Thermal stabilities and photoluminescent properties of 1 and 2 have also been investigated.

ChemInform Abstract: Perchloric Acid Modified‐Cellulose: A Versatile, Novel and Biodegradable Heterogeneous Solid Acid Catalyst for Single‐Pot Synthesis of Novel Bis‐pyran Annulated Heterocyclic Scaffolds under Solvent‐Free Conditions.

AbstractThe reaction of nitriles (II) with aryl mono‐ and dialdehydes and a variety of C—H‐acidic substrates gives the pyran‐annulated products in excellent yields.

ChemInform Abstract: Nucleophilic Addition Reactions of Nitriles to Nitrones under Mild Silylation Conditions.

AbstractThe synthetic versatility of the addition products is further examined by the transformation of the cyano group in (XIa) into a carboxamide, a carboxylic acid or an aminomethyl functionality.

A straightforward metal-free synthesis of 2-substituted thiazolines in air

A range of 2-substituted 4,5-dihydrothiazoles was easily synthesised from the reaction of nitriles with cysteamine in the presence of a catalytic amount of NaOH.

Infrared study of matrix-isolated ethyl cyanide: simulation of the photochemistry in the atmosphere of Titan.

Low-temperature Ar matrix isolation has been carried out to investigate the infrared spectrum of ethyl cyanide (CH3CH2CN), a molecule present in the atmosphere of Titan. The λ > 120 nm and λ > 230 nm photolysis reactions of ethyl cyanide in an Ar matrix were also performed in order to compare the behaviour of this compound when it is submitted to high and low energetic radiations. These different wavelengths have been used with the aim to reproduce the radiation reaching the various parts of the atmosphere. Several photoproducts have been identified during photolysis such as vinyl cyanide (CH2[double bond, length as m-dash]CHCN), cyanoacetylene (HC3N), and ethylene/hydrogen cyanide (C2H4/HCN), ethylene/hydrogen isocyanide (C2H4/HNC), acetylene/hydrogen cyanide (C2H2/HCN), acetylene/hydrogen isocyanide (C2H2/HNC), and acetylene:methylenimine (C2H2:HNCH2) complexes. Ethyl isocyanide (CH3CH2NC) and a ketenimine form (CH3CH[double bond, length as m-dash]C[double bond, length as m-dash]NH) have been identified as well. Photoproduct identification and spectral assignments were done using previous studies and density functional theory (DFT) calculations with the B3LYP/cc-pVTZ basis set.

A rapid metal free synthesis of 5-substituted-1H-tetrazoles using cuttlebone as a natural high effective and low cost heterogeneous catalyst

A convenient, rapid and metal free synthesis of 5-substituted-1H-tetrazoles by [3 + 2] cycloaddition reaction of nitriles with sodium azide. Cuttlebone as a natural low cost heterogeneous catalyst affords 5-substituted-1H-tetrazoles rapidly with high efficiency.