Alkoxy Alcohols Research Articles

Electrical Conductivity of Ionic Liquids 1-Hexyl-3-Methylimidazolium Chloride (HMIM) and 1-Methyl-3-Octylimidazolium Chloride (OMIM) in Mixtures with Selected Alkoxy Alcohols over a Wide Temperature Range

Ionic liquids have been the subject of intense research because of their unique electrochemical properties and potential applications in various fields. In this article, we analyze the electrical conductivity of two selected ionic liquids, 1-hexyl-3-methylimidazolium chloride (HMIM) and 1-eethyl-3-octylimidazolium chloride (OMIM), in various alkoxy alcohols such as 2-methoxyethanol, 2-ethoxyethanol, 2-propoxyethanol and 2-butoxyethanol. Our research focuses on attempting to analyze the impact of the molecular structure of both the ionic liquids and alkoxy alcohols on their electrical conductivity properties. The results of our study can be highly beneficial in the design of advanced electrochemical materials and their various applications.

Cation–anion confined hydrogen-bonding catalysis strategy for ring-closing C–O/O–H metathesis of alkoxy alcohols under metal-free conditions

Cation–anion confined hydrogen-bonding-catalyzed ring-closing C–O/O–H metathesis of alkoxy alcohols to O-heterocycles is realized over OH-functionalized ionic liquids under metal-free and mild conditions (≥70 °C).

Benzonorbornadien Oksit’in Mikrodalga Destekli ve Montmorillonite-K10 Katalizli Alkolizi: Wagner–Meerwein Düzenlenmesi ile Regioseçici Yeni Alkoksi Alkollerin Sentezi

Bu çalışmada, benzonorbornadien epoksitinin alkollerle mikrodalga destekli halka açılma tepkimeleri incelendi. Ucuz ve çevreci heterojen montmorillonite-K10 katalizörü eşliğinde yüksek verim ile kısa reaksiyon süresinde (10 dakikaya kadar) Wagner–Meerwein düzenlenmesi ile regioseçici olarak yeni alkoksi alkoller sentezlendi. Ürünler sadece süzme ile saflaştırıldı.

VOLUMETRIC AND VISCOMETRIC DETERMINATION OF BINARY LIQUID MIXTURES OF 2-ETHOXYETHANOL AND AMYL ACETATE AT TEMPERATURES OF (298.15 AND 303.15) K

Densities and viscosities have been determined at temperatures of (298.15 and 303.15) K for binary liquid mixtures of 2-ethoxyethanol with amyl acetate over the entire range of solvent composition. From the experimentally determined values, excess molar volume, VE, excess viscosity, ηE and excess Gibbs free energy of activation of viscous flow, G*E have been calculated. These calculated excess thermodynamic functions were fitted to Redlich-Kister polynomial equation to obtain the fitting coefficients and standard deviations. The values of excess molar volume, VE were negative and that of the excess viscosities, ηE were found to be positive, while excess Gibbs free energy of activation of viscous flow, ΔG*E were negative over the whole range of solvent composition for the binary systems at the studied temperatures. The behavior of these excess functions with composition of the mixtures have been discussed in respect of molecular interactions between the components of liquid systems. The mixture viscosities were correlated using empirical relations like Grunberg-Nissan, Frenkel, Hind, Wijk and Kendall-Monroe model equations. Comparison of these interaction parameters have been engaged to explain the intermolecular interactions between the alkoxy alcohol and the ester.

Hydrophobization of arabinoxylan with n-butyl glycidyl ether yields stretchable thermoplastic materials

Hemicelluloses are regarded as one of the first candidates for the development of value-added materials due to their renewability, abundance, and functionality. However, because most hemicelluloses are brittle, they can only be processed as a solution and cannot be processed using industrial melt-based polymer processing techniques. In this study, arabinoxylan (AX) was hydrophobized by incorporating butyl glycidyl ether (BuGE) into the hydroxyl groups through the opening of the BuGE epoxide ring, yielding alkoxy alcohols with terminal ethers. The formed BuGE derivatives were melt processable and can be manufactured into stretchable thermoplastic films through compression molding, which has never been done before with hemicellulose modified in a single step. The structural and thermomechanical properties of the one-step synthesis approach were compared to those of a two-step synthesis with a pre-activation step to demonstrate its robustness. The strain at break for the one-step synthesized AX thermoplastic with 3 mol of BuGE is ≈200%. These findings suggest that thermoplastic polymers can be composited with hemicelluloses or that thermoplastic polymers made entirely of hemicelluloses can be designed as packaging and stretchable electronics supports.

Thermo-physical and spectral investigations of binary liquid mixture of 2-(2-butoxyethoxy) ethanol with alcohols at temperature range of 293.15 K to 313.15 K

In continuation to our prior investigational studies on the interactions between binary mixtures of alkoxy alkanols and alcohols, here, we report density, speed of sound, FT-IR as well as NMR analysis of 2-(2-butoxyethoxy) ethanol, CH3(CH2)3OC2H4O(CH2)2OH, viz., 1-propanol CH3(CH2)2OH, 2-propanol (CH3)2CHOH, 1-butanol CH3(CH2)3OH and 2-butanol CH3CH2CH(OH)CH3. The experimental data of densities and speeds of sound over the entire composition range at 293.15, 298.15, 303.15, 308.15 and 313.15 K were used to calculate the values of excess functions and deviations in properties. Utilizing the spectroscopic analysis, chemical shift/frequency was accounted. The evaluated properties from experimental data have been construed in terms of the difference in the size of the molecule as well as the strength of specific and non-specific interactions between components of the mixture. The excess functions and their deviations have also been correlated using Redlich-Kister type polynomial equation by the method of least-squares for the estimation of the binary coefficients and the standard deviations.

FT-IR studies and excess thermodynamic properties of binary liquid mixtures 2-(2-butoxyethoxy) ethanol with 1-hexanol, 1-octanol and 1-decanol at different temperatures

Abstract In continuation to our prior investigational studies on the interactions between binary mixtures of alkoxy alkanols and alcohols, here, we report the thermo-physical properties and spectra analysis of 2-(2-butoxyethoxy) ethanol with CH3(CH2)3OC2H4O(CH2)2OH, viz., 1-hexanol CH3(CH2)5OH, 1-octanol CH3(CH2)7OH and 1-decanol CH3(CH2)9OH over the entire composition range at T = (293.15, 298.15, 303.15, 308.15 and 313.15) K. The experimental data of densities and speeds of sound were used to calculate the values of excess functions and deviations in properties. The evaluated properties from experimental data have been construed in terms of the difference in the size of the molecule as well as the strength of specific and non-specific interactions between components of the mixture. The excess functions and their deviations have also been correlated using Redlich-Kister type polynomial equation by the method of least-squares for the estimation of the binary coefficients and the standard deviations. The FT-IR technique has been used to scrutinize the –OH interactions between the binary mixtures and inestimable to spot the influence on the structural variation in the alcohols.

An Fe3O4 nanoparticle-supported Mn (II)-azo Schiff complex acts as a heterogeneous catalyst in alcoholysis of epoxides

In this paper, an azo-containing Schiff base complex of manganese [Mn 2+ -azo ligand@APTES-SiO 2 @Fe 3 O 4 ] immobilized on chemically modified Fe 3 O 4 nanoparticles has been used as a magnetically retrievable catalyst for the alcoholysis of different epoxides to their corresponding alkoxy alcohols with methanol, ethanol and n -propanol. The newly magnetic nanoparticles (MNPs) were characterized by Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX) and vibrating sample magnetometry (VSM).

Cross metathesis of unsaturated epoxides for the synthesis of polyfunctional building blocks.

The cross metathesis of 1,2-epoxy-5-hexene (1) with methyl acrylate and acrylonitrile was investigated as an entry to the synthesis of polyfunctional compounds. The resulting cross metathesis products were hydrogenated in a tandem fashion employing the residual ruthenium from the metathesis step as the hydrogenation catalyst. Interestingly, the epoxide ring remained unreactive toward this hydrogenation method. The saturated compound resulting from the cross metathesis of 1 with methyl acrylate was transformed by means of nucleophilic ring-opening of the epoxide to furnish a diol, an alkoxy alcohol and an amino alcohol in high yields.

Anomaly in dielectric relaxation dispersion of glass-forming alkoxy alcohols.

The dielectric relaxations in six primary and secondary alkoxy alcohols with varying molecular size and different separation between -O- and hydroxyl group are studied at temperatures around glass transition. The analyses of the apparent full width at half maximum of the main relaxations of the alkoxy alcohols reveal minima in the temperature dependence of the relaxation dispersions. The stretching exponents for the main relaxations of the alkoxy alcohols are also found not to follow the empirical correlations with other dynamic quantities established for generic liquids. A comparison of the relaxation dispersions in the alkoxy alcohols with those in Debye and non-Debye (generic) liquids is presented. The impacts of the β-relaxations on the apparent main relaxation widths are reviewed for molecular glass formers.

Ring-Opening of Oxiranes using Taeniolite-Supported Tris(β-Diketonato)Zirconium

A series of tris(β-diketonato)zirconium(IV) complexes was immobilized into a synthetic clay structure of Taeniolite by an ion-exchange method to generate organic/inorganic hybrid compounds. The hybrid compound served as a good catalyst for ring-opening reactions of methyl, ethyl, and dimethyl oxiranes with various alcohols to generate primary alkoxy alcohols in appreciable selectivity. This method describes a technique to immobilize cationic zirconium complexes without losing selectivity.

Zirconyl triflate, [ZrO(OTf)2], as a new and highly efficient catalyst for ring-opening of epoxides

A highly efficient method for the ring opening of epoxides catalyzed by ZrO(OTf)2 was adopted. This catalyst efficiently catalyzed alcoholysis, acetolysis and hydrolysis of epoxides and the corresponding alkoxy alcohols, acetoxy alcohols and 1,2- diols were obtained in excellent yields. Conversion of epoxides to 1,2-diacetetes, thiiranes and 1,3-dioxolanes was also performed in the presence of catalytic amounts of ZrO(OTf)2, and the corresponding products were obtained in high to excellent yields. The high catalytic activity of ZrO(OTf)2 is due to the replacement of Cl with OTf, which makes the ZrO(OTf)2 as efficient Lewis acid.

Efficient alcoholysis of 5,6-dihydro-1,10-phenanthroline-5,6-epoxide with ytterbium(III) triflate and subsequent enantioselective transesterification with lipases

New 5,6-dihydro-1,10-phenanthroline derivatives were prepared in high yield via ytterbium(III) triflate-catalyzed alcoholysis of the corresponding epoxide. Enzymatic transesterifications of racemic alkoxy alcohols afforded enantioselective separations with up to 99% ee. The lipase derived from Burkholderia cepacia (PSCI) was the most efficient, with E-values of up to 200. The steric effect of substituents in the 6-position on reaction time and enantioselectivities was assessed.

From vanadium(V) to vanadium(IV) - and backwards

With bidentate alkoxy alkoxide and alkoxy alcohol ligands, respectively, a series of oxovanadium complexes in the oxidation state +4 is synthesized starting from oxovanadium(V) compounds. The reaction of two or more equivalents of 2-methoxyethanol with VOCl3 in n-hexane yields a mixture of the monomeric oxovanadium(IV) complex cis-[VOCl2(HOCH2CH2OMe-κ2O)(HOCH2CH2OMe-κO1)] and the alkoxide-bridged oxovanadium(IV) dimer syn-[VOCl(µ-OCH2CH2OMe-κ2O)]2, which are separated by fractionated crystallization. The same reaction with 2-ethoxy- and 2-iso-propoxyethanol gives only the alkoxide-bridged oxovanadium(IV) dimers anti-[VOCl(µ-OCH2CH2OR-κ2O)]2 (R = Et, iPr). All alkoxide bridged oxovanadium(IV) dimers are furthermore obtained as decomposition products of the chloride-bridged oxovanadium(V) complexes [VO(µ-Cl)Cl(OCH2CH2OR-κ2O)]2 (R = Me, Et, iPr) by Cl2 elimination and react inversely with Cl2 to the vanadium(V) compounds.

Meta Halogenation of 1,3-Disubstituted Arenes via Iridium-Catalyzed Arene Borylation

We report the meta halogenation of 1,3-disubstituted arenes to form 3,5-disubstituted aryl bromides and chlorides by using iridium-catalyzed arene borylation chemistry. Iridium-catalyzed borylation of arenes with B2pin2, followed by reaction of the boronic ester with copper(II) bromide or chloride converts arylboronic esters to the corresponding aryl halides. A variety of arenes containing alkoxy, alkyl, halogen, nitrile, ester, amide, and pivaloyl and TIPS-protected alcohols were converted to the corresponding 3,5-disubstituted aryl bromides and chlorides in yields ranging from 46% to 85%. In addition, 2,6-disubstituted and 3-substituted pyridines were converted to the 4-halo and 5-halopyridines, respectively. The utility of this methodology was demonstrated by the formal conversion of nicotine to Altinicline in three steps with an overall yield of 61% using meta bromination of nicotine as the first step.

Zinc perchlorate hexahydrate [Zn(ClO 4) 2·6H 2O] as acylation catalyst for poor nucleophilic phenols, alcohols and amines: Scope and limitations

Commercially available zinc perchlorate hexahydrate [Zn(ClO 4) 2·6H 2O] was found to be a highly efficient catalyst for acylation of electron deficient phenols, sterically hindered alcohols and electron deficient and sterically hindered amines. The acetylated derivatives were obtained in excellent yields under solvent-free conditions and at room temperature. However, the reaction of highly electron deficient and sterically hindered phenol, e.g., 2,4-dinitrophenol required heating at 80 °C. In case of reactions with alkoxy or dialkoxy benzylic alcohols, a complex product mixtures were formed containing the corresponding dibenzylic ethers. The catalyst was found to be of general use with respect to other acylating agents such as propionic, iso-butyric, pivalic, benzoic and chloroacetic anhydrides. However, the rate of acylation was influenced by the steric and electronic factors of the anhydrides and followed the order Ac 2O > (PhCO) 2O > (EtCO) 2O > ( i PrCO) 2O > ( t BuCO) 2O ≫ (ClCH 2CO) 2O. Benzoylation and pivalation of phenols (including electron deficient phenols), dihydric phenol and sterically hindered alcohol afforded excellent yields. The catalytic activity of various zinc compounds was found to be of the order Zn(ClO 4) 2·6H 2O > ZnI 2 ∼ ZnBr 2 > ZnCl 2 ≫ Zn(OAc) 2 > ZnCO 3 and was parallel to the acidic strength of the corresponding protic acids.

Polymer supported ferric chloride: Regiospecific nucleophilic ring opening of epoxides

Cross-linked polystyrene, 4-vinyl pyridine copolymer beads were prepared, characterized and were used to complex ferric chloride. This polymer metal complex was used as a heterogeneous, recoverable and reusable Lewis acid in nucleophilic ring opening of different epoxides to prepare β alkoxy alcohols and β azidohydrins in good to excellent yields.

Alcoholysis of epoxidized polyisoprenes by direct opening of oxirane rings with alcohol derivatives 1. Modelization of the reaction

Alcoholysis of 4,5-epoxy-4-methyloctane selected as a model molecule of epoxidized 1,4-polyisoprene was achieved with various alcohols using cerium ammonium nitrate as catalyst. Next to the expected alkoxy alcohol, side products resulting from oxirane rearrangement were identified: 5-methyloctan-4-one, 5-methyloct-5-en-4-ol and 2- n-propylhexen-3-ol. One of them, 5-methyloct-3-en-4-ol, was demonstrated to be able to react with alcohols so leading to the formation of allylic ethers. From the diastereoisomer distribution, as well as the effect of temperature and solvent on the reaction, a coordinative S N2 mechanism able to explain the formation of the various products identified, is suggested.

ChemInform Abstract: Rhodium-Catalyzed Ring Opening of Vinyl Epoxides with Alcohols and Aromatic Amines.

[Rh(CO)2Cl]2 is an effective catalyst for the ring opening of vinyl epoxides with alcohols and aromatic amines under neutral conditions at room temperature. The reaction occurs with excellent diastereo- and regioselectivity (>20:1) giving the trans-1,2-amino alcohols or alkoxy alcohols for a wide range of substrates. The regio- and stereochemistry of these reactions is complementary to that typically obtained with palladium-catalyzed ring openings of vinyl epoxides.

Rhodium-catalyzed ring opening of vinyl epoxides with alcohols and aromatic amines

[Rh(CO)(2)Cl](2) is an effective catalyst for the ring opening of vinyl epoxides with alcohols and aromatic amines under neutral conditions at room temperature. The reaction occurs with excellent diastereo- and regioselectivity (>20:1) giving the trans-1,2-amino alcohols or alkoxy alcohols for a wide range of substrates. The regio- and stereochemistry of these reactions is complementary to that typically obtained with palladium-catalyzed ring openings of vinyl epoxides.