Oxime Methyl Ether Research Articles

Liquid–Liquid Equilibrium for the Ternary System Acetone Oxime Methyl Ether–Acetone–Water

In the production of acetone oxime methyl ether (AOME) and its related products, AOME usually needs to be separated from the AOME, acetone, and water mixture. As the base data, the liquid–liquid equilibrium data for the AOME–acetone–water ternary system were measured at 293.15 K, 303.15 K, 313.15 K, and 323.15 K, respectively, under atmospheric pressure. Then, the nonrandom two-liquid (NRTL) and T-K-Wilson models were used to correlate the experimental data. The root-mean-square deviation (RMSD) between the calculated values and the experimental data is less than 0.0054 for the NRTL equation, and the RMSD is up to 0.046 for T-K-Wilson equation. Therefore, for this ternary system, the NRTL equation is more suitable than the T-K-Wilson equation for predicting liquid activity coefficients of the system. At the same time, the experimental data also show that the temperature has little effect on the miscibility gap within the experimental temperature range.

Isobaric vapor–liquid equilibria of the binary system acetone + acetone oxime methyl ether at 101.3 kPa

Isobaric vapor–liquid equilibria (VLE) were measured for the binary system acetone+acetone oxime methyl ether (AOME) at 101.3kPa. The activity coefficients were correlated satisfactorily with NRTL and Wilson models. The thermodynamic consistency of the obtained VLE data was checked by Herington method and passed the test. The results show that the correlated data of NRTL and Wilson models are both in keep with the experimental data, and the UNIFAC parameters of the new group (CN) were determined using the obtained VLE data. The azeotrope behavior is not happen for the binary system of acetone+AOME, which can provide the basis data to design the separation process, and promote the development of new technology to produce O-methylhydroxyamine hydrochloride effectively and economically.

ChemInform Abstract: Chemoenzymatic Synthesis of 1,2- and 1,3-Amino Alcohols and Their Use in the Enantioselective Reduction of Acetophenone and anti-Acetophenone Oxime Methyl Ether with Borane.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Photochemical reactivity of 1-substituted-1-aza-1,4-dienes promoted by electron-acceptor sensitizers. Di-pi-methane rearrangements and alternative reactions via radical-cation intermediates.

Irradiation of a series of beta,gamma-unsaturated imines, oxime acetates, and oxime methyl ethers, using 9,10-dicyanoanthrathene (DCA) or dicyanodurene (DCD) as electron acceptor sensitizers, affords the corresponding cyclopropanes resulting from 1-aza-di-pi-methane rearrangements via radical cations. In some cases, alternative reactions of these intermediates occur to yield nitriles, dihydroquinolines, dihydronaphthalene derivatives, and cycloaddition products. Some of these products result from reactions via alkene radical-cation intermediates while others arise by pathways involving imine radical-cation intermediates. The yields of products formed in these processes were significantly higher when DCD was used as electron-acceptor sensitizer instead of DCA.

BrF3, an underutilized reagent in organic chemistry: a novel C-C-N to C-N-C rearrangement.

Little is known about bromine trifluoride in organic chemistry. Under the right conditions, it can be a useful tool and generate a new and unprecedented chemistry. Thus, when reacted with oxime methyl ethers of alpha-ketoesters, BrF3 was able to convert the oxime group into a CF2 group and through a new type of rearrangement cause a shift of the carboxylate group to the nitrogen atom. The novel structure of the alpha,alpha-difluorocarbamate was also proven by 15N NMR as demonstrated for compounds 3, 8, 9, 12, 15, and 18. Another novel "double rearrangement" was observed during the formation of 19. Dynamic 19F NMR experiments indicate a high nitrogen inversion-rotation (NIR) barrier for these novel carbamates of about 12.5 kcal/mol.

Synthesis of 14C‐labeled S‐(‐)‐1‐phenylethylamine and its application to the synthesis of [14C] CI‐1021, a potential antiemetic agent (1)

S-(-)-1-[U-ring-14C]phenylethylamine 3 was synthesized through the enantioselective borane reduction of E-[U-ring-14C]acetophenone oxime methyl ether derived from [U-ring-14C]acetophenone. The overall radiochemical yield was 66.7%. The enantiomeric excess (ee) was 96.60%. Coupling the labeled amine 3 with (R)-N-[(benzo[b]furan-2-ylmethoxy)-carbonyl-2-methyltryptophan 4 provided [R-(R*,S*)]{1-(1H-indole-3-ylmethyl)-1-methyl-2-oxo-2-[(1-[U-ring-14C]phenylethyl) amino]ethyl} carbamic acid benzo[b]furan-2-ylmethyl ester (CI-1021), a potential antiemetic agent. Copyright © 2000 John Wiley & Sons, Ltd.

Synthesis, structure and comparative stability of β-hydrazono, oximino methyl ether and imino boronates

β-Hydrazono and oximino ether boronates have been prepared by the sequential lithiation of the corresponding methyl hydrazone or oxime methyl ether, followed by reaction with an iodomethylboronate ester, typically in the form of the pinacol ester. The resulting products have contrasting hydrolytic stabilities. β-Hydrazono boronates are highly sensitive to intramolecularly catalysed hydrolysis, providing the corresponding β-keto boronates in generally high yields; β-oximino ether boronates are stable to silica gel chromatography and show evidence of E–Z-isomerisation. Stable homochiral boronate ester derivatives of β-oximino ethers can be readily prepared by a double transesterification process, via a diethanolamine-mediated pinacol ester exchange, followed by diethanolamine ester hydrolysis–reesterification process with a homochiral diol. β-Imino boronates can be generated in situ by condensation of the corresponding β-keto boronate with a primary amine, however the resulting imine function is highly hydrolytically unstable and cannot be isolated in a pure form.

Synthesis of14C-labeled S-(-)-1-phenylethylamine and its application to the synthesis of [14C] CI-1021, a potential antiemetic agent (1)

S-(-)-1-[U-ring-14C]phenylethylamine 3 was synthesized through the enantioselective borane reduction of E-[U-ring-14C]acetophenone oxime methyl ether derived from [U-ring-14C]acetophenone. The overall radiochemical yield was 66.7%. The enantiomeric excess (ee) was 96.60%. Coupling the labeled amine 3 with (R)-N-[(benzo[b]furan-2-ylmethoxy)-carbonyl-2-methyltryptophan 4 provided [R-(R*,S*)]{1-(1H-indole-3-ylmethyl)-1-methyl-2-oxo-2-[(1-[U-ring-14C]phenylethyl) amino]ethyl} carbamic acid benzo[b]furan-2-ylmethyl ester (CI-1021), a potential antiemetic agent. Copyright © 2000 John Wiley & Sons, Ltd.

ChemInform Abstract: Synthesis of Heterodiquinanes by Photoreaction of β‐Keto Esters with Oxime Methyl Ethers Derived from 3‐Acyl‐1,2‐dihydrocinnoline‐1,2‐dicarboximides.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Synthesis of Heterodiquinanes by Photoreaction of β-Keto Esters with Oxime Methyl Ethers Derived from 3-Acyl-1,2-dihydrocinnoline-1,2-dicarboximides

Abstract Photoreaction of hydrazodicarboximide with β-keto esters in acetonitrile in the presence and absence of triethylamine afforded intriguing heterodiquinane-based tricycles in moderate yields, together with both rearranged and dimeric products.

Flash Vacuum Thermolysis of Phenylcyclopropanecarbaldoximes and Its Methyl Ethers

AbstractFlash vacuum thermolysis of 1‐phenylcyclopropane‐1‐carbaldoxime at 500 °C produced mainly 3‐phenylpyrrole. The products after thermolysis of its oxime methyl ether were α‐methoxymethylstyrene, α‐methylstyrene, and a dimer 2,5‐dipheny 1‐1,5‐hexadiene.

2-Cyanoethyl and p-nitrophenethyl α-hydroxyimino- and α-methoxyimino-phosphonates: potential precursors of metaphosphate anion

Methyl benzoylphosphonochloridate 3 reacted with 2-cyanoethanol or p-nitrophenethyl alcohol to yield methyl 2-cyanoethyl benzoylphosphonate 4a or methyl p-nitrophenethyl benzoylphosphonate 4b. Ketones 4a and 4b were converted into the corresponding oximes, 5a and 5b as a mixture of E and Z isomers, by hydroxylamine. Oximes 5a and 5b were demethylated by treatment with sodium iodide or lithium bromide to give the corresponding monester monosalts 6a and 6b. Reaction of lithium 2-cyanoethyl or p-nitrophenethyl benzoylphosphonate with methoxylamine afforded the respective oxime methyl ether salts 8a and 8b as predominantly E isomers. Base treatment of 6a and 6b caused their dealkylation to the anion of α-hydroxyiminobenzylphosphonic acid 9 which did not decompose further. In contrast, 8a and 8b in aqueous base gave the dianion of α-methoxyaminobenzylphosphonic acid 10, which slowly fragmented to benzonitrile and phosporic acid. The fragmentation is interpreted in terms of a dissociative mechanism involving the formation of metaphosphate anion.

Chemo-enzymatic synthesis of 1,2- and 1,3- amino-alcohols and their use in the enantioselective reduction of acetophenone and anti-acetophenone oxime methyl ether with borane.

New chiral amino-alcohols were enantioselectively synthesized using biotransformations as the key steps. They were used as ligand in the enantioselective borane reduction of acetophenone and of the corresponding anti oxime methyl ether.

Photochemistry of α‐oxo oximes. Part 10: Photochemistry of three cyclic α‐oxo oxime methyl ethers and their acyclic analogue at λ 254 nm

AbstractThe (E)‐ and (Z)‐isomers of the 3,3,n,n‐tetramethyl‐2‐(methoxyimino)‐1‐cycloalkanones (n = 5 to 7) (3a‐c) and their acyclic analogue (Z)‐4‐(methoxyimino)‐2,2,5,5‐tetramethyl‐3‐hexanone [(Z)‐4] have been irradiated at λ 254 nm in acetonitrile as solvent in order to study the influence of ring size on product formation. The dependence of product composition on irradiation time revealed that the (E)‐isomers of 3a‐c undergo both E‐Z isomerization and photodecomposition, whereas the (Z)‐isomers undergo only Z‐E isomerization. The primary step in photodecomposition is homolysis of the NO bond. The observed products result from the various possible reactions of initially formed methoxy and cyclic iminyl radicals 17, cyanoacyl radicals 18 formed by ring opening of 17, cyanoalkyl radicals 19 formed from 18 by decarbonylation and cyclopentaniminyl radical 20b, formed by cyclization of the 5‐cyano‐2‐hexyl radical 19b. Mechanisms for the formation of the various products are proposed and the relative importance of the various steps is discussed, also in relation to the results obtained using carbon tetrachloride as radical scavenger.Irradiation of (Z)‐4 at λ 254 nm leads to decomposition with formation of 2,2‐dimethylpropanenitrile, methanol, isobutane and isobutene.

Carbon-13 NMR of para-substituted hydrazones, phenylhydrazones, oximes, and oxime methyl ethers: substituent effects on the iminyl carbon

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCarbon-13 NMR of para-substituted hydrazones, phenylhydrazones, oximes, and oxime methyl ethers: substituent effects on the iminyl carbonMichael S. Gordon, Stanley A. Sojka, and Josef G. KrauseCite this: J. Org. Chem. 1984, 49, 1, 97–100Publication Date (Print):January 1, 1984Publication History Published online1 May 2002Published inissue 1 January 1984https://doi.org/10.1021/jo00175a019RIGHTS & PERMISSIONSArticle Views627Altmetric-Citations47LEARN 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 (427 KB) Get e-Alerts Get e-Alerts