N-monosubstituted Amides Research Articles

Synthesis of N-Sulfonyl Amidines and Acyl Sulfonyl Ureas from Sulfonyl Azides, Carbon Monoxide, and Amides.

A Pd-catalyzed and ligand-free carbonylation/cycloaddition/decarboxylation cascade synthesis of sulfonyl amidines from sulfonyl azides and substituted amides at low CO pressure is reported. The reaction proceeds via an initial Pd-catalyzed carbonylative generation of sulfonyl isocyanates from sulfonyl azides, followed by a [2 + 2] cycloaddition with amides and subsequent decarboxylation, which liberates the desired sulfonyl amidines, generating N2 and CO2 as the only reaction byproducts. Using this simple protocol, a diverse range of sulfonyl amidines was obtained in moderate to excellent yields. In addition, the reaction can also be directed through a more conventional amidocarbonylation pathway by employing N-monosubstituted amide nucleophiles to afford acyl sulfonyl ureas in good yields.

A route to simple nonionic surfactants

AbstractA method for the synthesis of nonionic surfactants – N-alkyl-O-(2-hydroxyethyl) carbamates is proposed by acylation of fatty amines with ethylene carbonate without any solvent or catalyst. The surface tension of the prepared surfactants was measured, toxicity and biodegradability were determined for the surfactant with n-dodecyl as a hydrophobic group and N-monosubstituted amide and hydroxyl groups for their hydrophilic part.

Metal-free hydration of ynamides: convenient approach to amides

The trifluoroacetic acid (TFA) mediated hydration of ynamides was developed, which is an efficient approach for the synthesis of N-monosubstituted amides. This convenient method is effective with a wide range of substrates under room temperature condition, and the products are obtained in high to excellent yields through an easy work-up process.

Structure-activity relationship studies on quinoxalin-2(1H)-one derivatives containing thiazol-2-amine against hepatitis C virus leading to the discovery of BH6870.

Chronic hepatitis C virus infection represents a serious global public health problem, typically resulting in fibrosis, cirrhosis, and ultimately hepatocellular carcinoma. Based on our previous discovery of lead compound 2 (Liu et al. J Med Chem 54:5747-5768, 2011), 35 new quinoxalinone derivatives were explored in this study. Outline of the structure-activity relationships (SARs) revealed that compound BH6870 (36) showed high anti-HCV potency ([Formula: see text]) and a good cell safety index (SI [Formula: see text]). SARs analysis indicated that quinoxalin-2(1H)-one containing a 4-aryl-substituted thiazol-2-amine moiety was optimal for antiviral activity. Introducing a hydrogen-bond acceptor (such as ester or amide group) at the C-3 position of quinoxalin-2(1H)-one was beneficial for the antiviral potency, and especially, N,N-disubstituted amide was far superior to N-monosubstituted amide. Incorporation of more than one halogen (fluorine or chlorine atom) or a strong electron-withdrawing group on the benzene ring of the thiazole-phenyl moiety might reduce electron atmosphere density further and resulted in a dramatical loss of activity. The NH-group of the lactam moiety was clearly required for anti-HCV activity. Design and synthesis of quinoxalin-2(1H)-one derivatives as new non-nucleoside small-molecule HCV inhibitors. BH6870 (36), showing higher antiviral potency and a good cell safety index, was identified.

New Way to Produce Magnetite Nanoparticles at Low Temperature

This work reports a simple process for preparation of stable and uniform magnetite nanoparticles (Fe3O4) at low temperature. The method is supported in three single steps and provides low-sized functionalized magnetite nanoparticles at lower temperatures than the obtained by similar methods. The samples have been characterized by x-ray diffraction (XRD), Fouriertransform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), and vibrating sample magnetometry (VSM), where it shows the nature of the nanoparticles. This study reveals that these nanoparticles are spherical in shape and have an average size of 30 nm, they present a super-paramagnetic behavior, and IR spectra show the group of N-monosubstituted amides, CO-NH in the cover of the superparamagnetic nanoparticles which avoids their agglomeration..

Reduction of Carboxylic Acid Derivatives Using Diphenylsilane in the Presence of a Rh–PPh3 Complex

Abstract Reductions of carboxylic acid derivatives by silanes in the presence of rhodium complexes were studied. Carboxylic esters were reduced to alcohols by diphenylsilane catalyzed by [RhCl(cod)]2/4PPh3 or [RhCl(PPh3)3] at room temperature in up to 99% yields. For example, ethyl decanoate and ethyl phenylacetate were converted to decanol and 2-phenylethanol in 98 and 92% yields, respectively. Carboxylic acids were also reduced by this reducing system to the corresponding alcohols in high yields. Furthermore, N-monosubstituted amides were reduced to secondary amines in moderate to good yields. For sterically hindered amides, the yields were moderate, and imines were produced in competitive yields.

Low‐Temperature Deacylation of N‐Monosubstituted Amides.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Acylurea Pyrolysis - Thermolysis of N,N′-Disubstituted Ferrocenoylureas as a New Way to N-Monosubstituted Ferrocenecarboxamides

Several N-monosubstituted amides of ferrocenecarboxylic acid were synthesized by pyrolysis of N,N'-disubstituted ferrocenoylureas in boiling dioxane under neutral conditions. The reaction time and the yield were found to be dependent on the nature of the substituents. For the species D1 and D4 a single crystal structure analysis was made. The structural effect of the twist between the amide plane and the cyclopentadienyl rings was investigated.

Low-Temperature Deacylation of N-Monosubstituted Amides

[reaction: see text] The (PhO)(3)P.Cl(2) reagent, prepared in situ by titrating a solution of triphenyl phosphite with chlorine, is used to convert N-monosubstituted amides into their corresponding amines. The reaction, if compared to other traditional methods, shows the advantage of very mild conditions and low temperature (-30 degrees C-->rt).

Characteristic distributions of negatively charged N-monosubstituted amide clusters generated by electron attachment in supersonic expansions

Negatively charged clusters of N-monosubstituted amide molecules [(XCO-NHY)n−; X, Y = H, CH3, C2H5] were formed by injecting slow electrons into the collision region of supersonic expansions. In addition to the dipole-bound dimer species reported by C. Desfrancois, V. Periquet, S. Carles, J. P. Schermann and L. Adamowicz [Chem. Phys., 1998, 239, 475], larger clusters up to n = 50 were created for the first time. Efficient formation of trimer anions was observed for ethyl substituted amides. With a threshold size of n = 6 or 7, prominent peaks of magic numbers were found for clusters of N-methylformamide and N-methylacetamide, whereas smoothly undulated size-distributions are developed for the ethyl substitutions. A pattern was found in the periodicity of the undulations, of which the span extends as the substituents become bulkier. A hypothetical structure for large clusters in a spiral arrangement is proposed from aspects of electrostatic interactions to make an agreement with the pattern.

Two approaches to α,α-bis-Mannich salts of N-monosubstituted amides

Two generally applicable syntheses of 2-bis-(dimethylaminomethyl)acetamides 9 are described. The first one involves reaction of N-mono substituted acetamides 3 with dimethyl(methylene)ammonium chloride in the presence of phosphorus oxychloride using diethyl ether as a solvent. Starting from ketoximes, the amines 9 are obtained under the same reaction conditions via Beckmann rearrangement. C-Aminomethylation observed in all cases may be the result of the formation of imidoyl chlorides 5 as intermediates.

Phase equilibria in binary systems containing N-monosubstituted amides and hydrocarbons

The binary vapour-liquid equilibrium of seven systems of ε-caprolactam + octane, + decane, + dodecane, octane, + decane, + dodecane, of N-methylacetamide + octane, of N-ethylacetamide of N-methylpropionamide + octane and of N-methylpropionamid + ε-caprolactam was measured in the temperature range from 363 to 423 K and in the low pressure region. A static equilibrium apparatus for the measurements was constructed. In the system N-methylpropionamide + octane measurements of liquid-liquid equilibrium were carried out in the temperature range from 310 K up to the critical solution temperature. The experimental results were correlated applying activity coefficients models such as NRTL. The data obtained from our measurements were used to estimate UNIFAC interaction parameters for the groups CH 2 CONHCH 2 , CH 2 C 5H 10CONH and CONHCH 2 C 5H 10CONH .

Hydrogen bonding of N-monosubstituted amides. IR and NMR study of N-butylbenzamides

The self-association through hydrogen bonding of N-butylbenzamides has been studied by infrared spectroscopy in carbon tetrachloride, chloroform and benzene. The spectroscopic characteristics and thermodynamic parameters for the self-association have been determined. Also, the carbon tetrachloride and chloroform solutions of the amides have been studied by 1H NMR spectroscopy. The equilibrium constants for self-association obtained by NMR technique are in good agreement with the corresponding values from infrared measurements.

A novel addition–rearrangement of O-(1-benzotriazolylalkyl)oximes with organolithium reagents. Convenient non-oxidative conversions of aldehydes into amides

Condensation of an aldehyde, an oxime and benzotriazole gives an O-(1-benzotriazolylalkyl)oxime which undergoes an addition–rearrangement on treatment with an organolithium reagent. This reaction provides a novel non-oxidative method for the transformation of aldehydes into amides which has afforded several new N-monosubstituted amides with crowded structures. Grignard reactions of the O-(1-benzotriazolylalkyl)oximes give alcohols as the major products.

Polymers and ceramics based on icosahedral carboranes. Model studies of the formation and hydrolytic stability of aryl ether, ketone, amide and borane linkages between carborane units

The synthesis and hydrolysis to free carborane (R–CB10H10C–H) and a carboxylate under alkaline but not neutral conditions, of five 1,2- and 1,7-carboranyl ketones (R–CB10H10C–CO-R′) is described in a study of the optimum sequence of ether, ketone, carborane and phenylene groups for poly(ether ketone)(PEK) polymers. 1, 2-Dicarba-closo-dodecaborane (12) behaves as a better leaving group than the 1, 7 isomer from a proposed intermediary anionic adduct of hydroxide to carbonyl carbon. 1-(4-Fluorophenyl)-1, 2-dicarba-closo-dodecaborane (12)(F-C6H4-CB10H10C-H) suffers cage degradation and not nucleophilic substitution with sodium phenoxide, precluding polymerisation by this method, but 1,2-carboranebenzoic acids (R–CB10H10C–C6H4–CO2H) condense cleanly with aryl ethers in trifluoromethanesulfonic acid (TFSA), as do phenoxyphenyl-1, 2-carboranes (R–CB10H10C–C6H4–O–C6H5) with benzoic acid. 1, 2- and 1, 7-carboranyl N-monosubstituted amides (R–CB10H10C–CO–NHR') hydrolyse relatively slowly to free carboranes (R–CB10H10C–H) and amines in alkali, suggesting initial deprotonation at NH rather than nucleophilic addition. Synthesis of four model boranes is described; those with 1, 2-carborane bonded to boron are readily hydrolysed by water, bis[1, 7-dicarba-closo-dodecaborane(12)yl]phenylborane [(H–CB10H10C–)2B–C6H5] reacts slowly, but 1, 7-bis(diphenylboryl) 1,7-dicarba-closo-dodecaborane(12)[(C6H5)2B – CB10H10C – B(C6H5)2] required alkaline conditions. Formation of free carboranes and B-hydroxy compounds is consistent with a mechanism analogous to hydrolysis of the corresponding ketones. The relative reactivities of the boranes correspond to the leaving-group abilities of the isomeric carboranes and the build-up of steric compression in a proposed tetrahedral borate intermediate. The most promising polymer structures are inferred from the hydrolytic experiments.

An efficient method for hydrolysis of N-monosubstituted amides utilization of intramolecular NO acyl migration in hydroxypivalimides

An efficient and versatile method for the hydrolysis of N-monosubstituted carboxamides has been developed. The method consists of two steps: the conversion to acetoxypivalimides (≥90% yield) and their mild alkaline hydrolysis (70∼90% yield). No epimerization at the α-position of the acyl group took place in the process. The amine part of the original amides can be recovered in good yield.

Hydrogen bonding of N-monosubstituted amides. Ir study of N-butylacetamides

The self-association through hydrogen bonding of four isomeric N-butylacetamides has been studied by infrared spectroscopy in carbon tetrachloride, chloroform and benzene. The spectroscopic and thermodynamic parameters for the self-association have been determined. It was found that self-association decreases in the order: N-n-butylacetamide〉N-isobutylacetamide〉N-sec-butylacetamide〉N-tert-butylacetamide. The equilibrium constants and enthalpies of self-association for chloroform and benzene solutions are significantly smaller than in carbon tetrachloride.

An efficient method for hydrolysis of N-monosubstituted amides via acetoxypivalimides

Various N-monosubstituted carboxamides were efficiently hydrolyzed in two steps through acetoxypivalimides. The method can he applied to a wide range of amides without racemization of α-position of the acyl groups. The amines can also be recovered.

Hydrogen bonding of N-monosubstituted amides. IR study of N-ethylacetamide and N-methylpropionamide

The thermodynamic parameters of N-ethylacetamide (NEA) and N-methylpropionamide (NMP) self-association in carbon tetrachloride, benzene and toluene were determined on the basis of IR spectroscopic data. Also, the present paper reports the spectroscopic and thermodynamic parameters for 1:1 amide - aromatic donor complexes.

Hydration of N-monosubstituted amides in the binary solvents dioxane-water-d2 and dioxane-water

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTHydration of N-monosubstituted amides in the binary solvents dioxane-water-d2 and dioxane-waterMitsue. Kobayashi and Kohji. NishiokaCite this: J. Phys. Chem. 1987, 91, 5, 1247–1251Publication Date (Print):February 1, 1987Publication History Published online1 May 2002Published inissue 1 February 1987https://doi.org/10.1021/j100289a041RIGHTS & PERMISSIONSArticle Views205Altmetric-Citations15LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (494 KB) Get e-Alerts