Aliphatic Dicarboxylic Acids Research Articles

Renewable (Bis)pyrrolidone Based Monomers as Components for Thermally Curable and Enzymatically Depolymerizable 2-Oxazoline Thermoset Resins

In this study we describe the synthesis of bis(pyrrolidone) based dicarboxylic acids from itaconic acid and their application in 2-oxazoline resins for fully renewable thermoset materials. The monomers are obtained using a bulk aza-Michael addition of a diamine and two itaconic acid molecules using a catalytic amount of water. The monomers can be isolated in high purity after recrystallization, though their yield proved to be highly dependent on the selected diamine spacer length: In general, only the dicarboxylic acids containing diamines with an even number of methylene spacers are isolated in high yields. Through NMR, GPC, and FTIR analysis we demonstrate that these bis(pyrrolidone) based dicarboxylic acids exhibit significantly enhanced curing rates in 2-oxazoline resins compared to resins containing aliphatic dicarboxylic acids such as sebacic acid. Overall, we demonstrate that the rate of 2-oxazoline ring-opening addition with carboxylic acid functionalities is determined by the used dicarboxylic acid, whereas the ring-opening addition of the 2-oxazoline functionality with amide groups is determined by the used bis(2-oxazoline) compound. The thermosets obtained after curing proved to be readily plasticized by water, opening up possibilities for enzymatic degradation.

Studies on the Synthesis of some new 1, 2, 4-Triazoles Derivatives and Evaluation for their Anti-Tubercular activity profiles

The synthesis of new heterocyclic compounds has always drawn the attention of medicinal chemist over the years mainly because they possess diverse biological properties. The literature survey on 1,2,4-triazoles revealed that they are endowed with wide variety of biological activities. During the present investigation a series of new 1,2,4-triazole derivatives N-(3-(2-(3-hydrazinyl-3-oxoalkanoyl)hydrazinyl)-5(phenoxymethyl)-4H-1,2,4-triazol-4-yl)isonicotinamide(6a-6e) were synthesized by reacting with N-(5-mercapto-3-(phenoxymethyl)-4H-1,2,4-triazol-4-yl)isonicotinamide (5) and aliphatic dicarboxylic acid hydrazides (a-e). The structures of the newly synthesized compounds were established by FT-IR, 1H-NMR and MASS spectral analysis. All the compounds synthesised 6a to 6e were evaluated for anti-tubercular activity against Mycobacterium tuberculosis H37Rv using MABA method. The compound 6a (n=0) was found to be the most potent anti-tubercular agent. Few of the other compounds in the series also showed significant anti-tubercular properties.

The only examples of cationic lanthanide pimelate frameworks decorated by π-conjugated 1,10-phenanthrolines

Abstract A series of lanthanide pimelates [Sm(phen)(Hpim)(pim)] n ·1.5nH 2 O ( 1 , phen = 1,10-phenanthroline, H 2 pim = pimelic acid), and [ Ln (phen)(pim)] n ·nClO 4 ·nH 2 O [ Ln = Gd ( 2a ), Tb ( 2b ), Er ( 2c )] have been hydrothermally synthesized and characterized structurally by elemental analysis, IR spectroscopy, thermogravimetric analysis and PXRD. Compound 1 contains 1-D neutral [Sm(phen)(Hpim)(pim)] n chain that is constructed by the linkages of [Sm(phen)] ions and pim 2− /Hpim − ligands, while compounds 2a - c contain 1-D cationic [ Ln (phen)(pim) + ] n chain with ClO 4− ion as counterion. Although a lot of lanthanide coordination polymers were obtained with aliphatic dicarboxylic acids, they usually show neutral frameworks. Compounds 2a - c provide the only examples of cationic lanthanide pimelate frameworks decorated by phen chromophores. The photoluminescent properties of 1 and 2b - c , and magnetic properties of all compounds have been studied.

Efficient One-pot HATU Mediated Coupling of Dicarboxylic Acid and Amines for the Synthesis of Diamide at Ambient Temperature

Background: Amide bond is prevalent in peptides. Moreover, at least 25% pharmaceutical products also contain amide bond. A wide ranging strategy including Ugi reaction and related multicomponent reactions is available for the synthesis of amide. While HATU mediated direct one-pot diamide synthesis is scarcely investigated in the literature. Objective: The objective of this work is to achieve a one pot synthesis of diamide using various coupling reagents. Method: Straightforward one-pot coupling of dicarboxylic acid with corresponding amine was accomplished in the presence of HATU under ambient condition using 2-Me THF as an industrial green solvent. Results: A range of (hetero)aromatic and aliphatic dicarboxylic acids were coupled with aromatic and aliphatic amines to give 55-89% yield of the products at ambient temperature. Conclusion: Among various coupling reagents scrutinized, HATU was proven to be ‘gold standard’ to accomplish one-pot synthesis of diamides. Keywords: Coupling reagents, diamide, HATU, one-pot, peptides, rt.

An Aliphatic Ester Diisopropyl Sebacate Exhibited an Adjuvant Effect on Fluorescein Isothiocyanate-Induced Contact Hypersensitivity Mouse Models.

Alternative plasticizers have become more popular due to health concerns about phthalate esters. We demonstrated that phthalate esters enhanced skin sensitization to fluorescein isothiocyanate (FITC) in mouse contact hypersensitivity models. Alternative plasticizers have not been well studied as to their effect on the immune system. We previously found that diisopropyl adipate (DIPA), an aliphatic dicarboxylic acid ester, enhanced skin sensitization to FITC. Sebacate esters are also widely used as alternative plasticizers. Here we tested diisopropyl sebacate (DIPS), which has the same alcohol with an aliphatic dicarboxylic acid of longer chain, using BALB/c mice. The results showed that DIPS facilitated skin sensitization to FITC and increased FITC-presenting dendritic cell trafficking from the skin to draining lymph nodes. Furthermore, DIPS activated transient receptor potential ankyrin 1 (TRPA1). The latter feature has been commonly observed for phthalate esters and DIPA, which have adjuvant effects. In summary, the adjuvant effect of a sebacate ester was demonstrated in a mouse model.

Perylene-based sulfonated aliphatic polyimides for fuel cell applications: Performance enhancement by stacking of polymer chains

Aliphatic-type sulfonated polyimides with different aliphatic chain lengths consisting of perylenediimide units have been facilely synthesized via mild polyacylation of a sulfonated diarene monomer and aliphatic perylenediimide dicarboxylic acid monomers. The membranes were prepared by casting from DMSO solutions. The obtained flexible and tough membranes exhibited distinct micro-phase separation and excellent proton conductivity while maintaining relative low linear swelling ratio. For example, the proton conductivity of 162.2mS/cm was obtained for membrane AL-SPI-10 (IEC = 1.73mmol/g) at 80°C with the lower linear swelling ratio of 27%. Moreover, The maximum power densities for the fuel cell based on AL-SPI-5 and AL-SPI-10 reached 931.88mW/cm2 and 773.51mW/cm2 at 80°C, respectively, The high performance of the membrane may be ascribed to the self-assembly behavior driven by the strong π-π interactions of the perylenediimide units and the hydrophilic interactions of the sulfonated groups.

Crystallization of polyesters composed of isohexides and aliphatic dicarboxylic acids: Effects of isohexide stereoisomerism and dicarboxylic acid chain length

We have investigated the crystallization of a series of bio-based polyesters made from isohexides [isomannide (M) or isosorbide (S)] and aliphatic dicarboxylic acids (Mk or Sk with k = 4, 5, 6, 8, 10, 12, where k is the carbon number of dicarboxylic acid units). The effects of stereoisomerism of isohexide units (M or S) and chain length of dicarboxylic acid units (k) on the crystallization of the polyesters were systematically examined. A crystalline nature of M4, M10, M12, S10, and S12 was confirmed by differential scanning calorimetry, wide-angle X-ray diffraction, and polarized optical microscopy. Especially, we performed detailed studies on the crystalline hierarchical structure and crystallization behavior of the crystalline polyesters with long dicarboxylic acid units (k ≥ 10). The larger k gave a higher crystallinity for both Mk and Sk (k = 10, 12), while a difference in crystallinity between Mk and Sk was not so large. The right-handed 2/1 helical conformation of M12 was proposed on the basis of the fiber diagram, infrared progression bands, and conformational analysis. The equilibrium melting temperatures of Mk and Sk (k = 10, 12) were determined to ca. 100 °C using the solvent-annealed samples. The crystallization rate drastically increased with increasing k, and the crystallization of Sk was faster than that of Mk.

Polyamides based on a partially bio-based spirodiamine

In this study novel, fully and partially bio-based polyamides containing spiroacetal moieties in the backbone derived from bio-glycerol and bio-ethanol were prepared and characterized. The renewable diamine employed to obtain a series of polyamides was synthesized by means of thiol-ene click chemistry and therefore contains flexible thioether as well as rigid spiroacetal moieties. Two different chemical pathways for the polymerization were investigated and evaluated. The polymerization of polyamide salts proved to be the most promising method and therefore salt polymerization was applied in the synthesis of polyamides with aliphatic and aromatic dicarboxylic acids. Subsequently, the structure of the polymers was confirmed by Maldi-ToF analysis and additionally thermal and mechanical properties were investigated revealing Tg’s between 24 and 80°C and ductile materials with moduli between 1.0 and 1.5GPa. Both semicrystalline and amorphous polyamides were thermally stable and therefore suitable for thermal processing. In the end, degradation studies were performed on the acetal containing polyamides which showed that the polymers were stable at pH 3 and higher.

Thermotropic liquid crystalline polyesters derived from 2-chloro hydroquinone

Synthesis of thermotropic liquid crystalline polyesters derived from bis[4-hydroxy benzoyloxy]-2-chloro-1,4-benzene (BHBOCB) and aliphatic dicarboxylic acid chlorides by interfacial polycondensation methodology is presented. Synthesised polyesters consist of bis[4-hydroxy benzoyloxy]-2-chloro-1,4-benzene as a mesogen and aliphatic diacid chloride as flexible spacer. The length of oligomethylene units in the polymer was varied from the trimethylene to the dodecamethylene groups. Synthesized polyesters were characterized by differential scanning calorimetry and optical microscopy. The transition temperatures and thermodynamic properties were studied for all these polymers. These polyesters exhibited thermotropic liquid crystalline behavior and showed nematic texture except decamethylene spacer. Decamethylene spacer based polyester showed marble texture of smectic C. Mesophase stability of these polyesters was higher than $$123{^{\circ }}\hbox {C}$$ (except first heating cycle of PE-1). SYNOPSIS The present study deals with the synthesis of thermotropic liquid crystalline polyesters derived from bis[4-hydroxy benzoyloxy]-2-chloro-1,4-benzene (BHBOCB) and aliphatic dicarboxylic acid chlorides by interfacial polycondensation methodology.

Crosslinking of Polyvinyl Alcohol (PVA) and Effect of Crosslinker Shape (Aliphatic and Aromatic) Thereof

In the presented work, the effect of crosslinker geometry on the properties of PVA is reported. The aliphatic (suberic) and aromatic (terephthalic) dicarboxylic acids are used as crosslinker molecules. On the basis of tensile test and thermal properties, it is observed that crosslinking of PVA by suberic acid is more effective than terephthalic acid. The maximum strength measured in crosslinked samples is 32.5 MPa for suberic acid crosslinked PVA which is higher than that of neat PVA (22.6 MPa). Swelling study shows that 8 h crosslinked terephthalic acid (35% w/w) samples have a minimum of 5.4% of water uptake compared to neat PVA, which dissolves readily in water. DTGA shows that the decomposition temperature of crosslinked PVA is 345 °C while neat PVA has a decomposition temperature of 315 °C. FTIR spectroscopy confirms the formation of crosslink ester bond in crosslinked PVA. The crosslinked samples kept for bio-degradation show maximum degradation in terephthalic acid (15% w/w) crosslinked PVA.

Itaconic acid used as a versatile building block for the synthesis of renewable resource‐based resins and polyesters for future prospective: a review

AbstractItaconic acid, a carbohydrate‐derived aliphatic dicarboxylic acid, is a potential chemical for the synthesis of renewable resource‐based resins and polyesters. Owing to environmental reasons, there is a gradual demand for renewable resources in the chemical industry. Conversely, as a rather underappreciated side effect of this growth, novel chemical building blocks are obtained, which are not commercially derived from petrochemical sources. In this respect, itaconic acid has attracted much attention and its trifunctional structure leads to the synthesis of novel polymeric materials. This review discusses the most relevant information for bio‐based resins and polyesters resulting from itaconic acid and distinctive properties for various commercial applications. © 2017 Society of Chemical Industry

Thermal degradation of random copolyesters based on 1,4-butanediol, terepthalic acid and different aliphatic dicarboxylic acids

Thermal stability and degradation kinetics have been studied for a series of aliphatic-aromatic copolyesters where the terephthalate content was varied between 30 mol-% and 70 mol-%. Succinate, adipate and sebacate were considered as the aliphatic dicarboxylate unit. All copolyesters were synthesized with a perfect random distribution by a thermal transesterification process from the corresponding homopolyesters.A complex degradation was deduced for all copolymers taking into account the increment of the activation energy with conversion. In fact, thermogravimetric curves showed a minor decomposition process in the low conversion region that was more significant for the succinate derivative and specifically for that having the lowest aromatic content. The sebacate derivative was characterized by the presence of an additional and minor decomposition process that took place at the highest conversion.All copolyesters were defined by a major decomposition process, which has similar values of activation energy regardless of the method used to calculate them (e.g. Kissinger, KAS or Friedman methodologies). This decomposition reaction followed a A4 Avrami-Erofeev mechanism when Coats-Redfern and Criado methodologies were applied. In summary, all the studied copolymers thermally decompose following a complex process but in all cases the main degradation step corresponds to a similar degradation mechanism.

Exploring binding preferences in co-crystals of conformationally flexible multitopic ligands

A series of conformationally flexible, bipyridine-based ligands were co-crystallized with nine aliphatic dicarboxylic acids of varying carbon chain lengths.

海洋および湖沼堆積物中の不溶性有機物(ケロジェン)のキャラクタリゼーション : アルカリKMnO_4酸化分解生成物の脂肪族ジカルボン酸の分子分布

海洋および湖沼堆積物中の不溶性有機物(ケロジェン)のキャラクタリゼーション : アルカリKMnO_4酸化分解生成物の脂肪族ジカルボン酸の分子分布

Enzyme-Mediated Enantioselective Hydrolysis of Aliphatic Dicarboxylic Acid Diesters

The enzyme-mediated highly enantioselective hydrolysis of aliphatic dicarboxylic acid diesters has been developed. The racemic diesters were easily prepared by the coupling of racemic alcohols with dicarboxylic anhydrides followed by esterification or with dicarboxylic acids. In the cases of bis(1-phenylethyl) glutarate and bis(1-phenylethyl) adipate, the diesters which contained the dl- and meso-form diastereomers, were enantioselectively hydrolyzed by lipase from Candida antarctica (Novozym 435) in buffer at 30°C to afford the almost optically pure (R)-1-phenylethanol. On the other hand, the following chemical hydrolysis of the remaining (S, S)-diesters and (S)-monoesters gave the (S)-alcohol. Finally, both enantiomers were stoichiometrically obtained in about 100% isolated yield based on the racemic diesters. The enzymatic reaction was also applicable for the preparation of several optically active alcohols. In some cases, both the reactivities and enantioselectivities were quite different from those in the case of the corresponding simple acetates.

SYNTHESIS AND CHARACTERIZATION OF BIO-BASED POLYESTER POLYOL

Polyurethanes are versatile polymeric materials and are usually synthesised by isocyanate reactions with polyols. Due to the variety of isocyanates and polyols, particularly polyols, polyurethanes can be easily tailored for wide applications, such as rigid and flexible foams, coatings, adhesives, and elastomers. Considerable efforts have been recently devoted to developing bio-based substitutes for petroleum-based polyuretahanes due to increasing concerns over the depletion of petroleum resources, environment, and sustainability. Polyester polyols based on aliphatic and aromatic dicarboxylic acids are one of the most important materials in polymer technologies. Large volume of plants oils are used as renewable resources to produce various chemicals which are industrially important to make soaps, cosmetic products, surfactants, lubricants, diluents, plasticizers, inks, agrochemicals, composite materials, food industry. This study introduces synthesis and properties of bio-based polyols from different renewable feedstocks including vegetable oils and derivatives. A comparison of bio-based polyol properties with their petroleum-based analogues were investigated.

Effects of the crystal structure and thermodynamic stability on solubility of bioactive compounds: DFT study of isoniazid cocrystals

Intrinsic solubility of the isoniazid-carboxylic acid cocrystals is explored using thermodynamic cycle of transferring from crystal to gas and then to solution. The enthalpy/Gibbs free energy of phase transitions is computed by solid-state DFT (crystal) and DFT methods with/without accounting for polar solvent (aqueous solution/gas). The dissolution process of the isoniazid-dicarboxylic acid 2:1 cocrystals is found to be enthalpy-determined. The linear correlation between the theoretical sublimation enthalpies and experimental Gibbs energy of solution is established. According to it, the increase of stability causes the decrease of the considered cocrystals solubility. We conclude that a soluble and relatively stable cocrystal of isoniazid should be characterized by the sublimation enthalpy varying from 185 to 200kJ·mol−1. Bader analysis of theoretical periodic electron density enables us to quantify the non-covalent interactions and clarify their role in formation of the isoniazid cocrystals. The sublimation enthalpy of the cocrystals is defined by the structure of the coformer molecule. Its value is less 150kJ·mol−1 in the case of aromatic acids and larger than 180kJ·mol−1 for the aliphatic dicarboxylic acids. The sublimation enthalpy increases with the increase of the dicarboxylic acid hydrocarbon chain.

Photoresponsive Liquid Crystalline Epoxy Networks with Shape Memory Behavior and Dynamic Ester Bonds.

Functional polymers are intelligent materials that can respond to a variety of external stimuli. However, these materials have not yet found widespread real world applications because of the difficulties in fabrication and the limited number of functional building blocks that can be incorporated into a material. Here, we demonstrate a simple route to incorporate three functional building blocks (azobenzene chromophores, liquid crystals, and dynamic covalent bonds) into an epoxy-based liquid crystalline network (LCN), in which an azobenzene-based epoxy monomer is polymerized with an aliphatic dicarboxylic acid to create exchangeable ester bonds that can be thermally activated. All three functional building blocks exhibited good compatibility, and the resulting materials exhibits various photomechanical, shape memory, and self-healing properties because of the azobenzene molecules, liquid crystals, and dynamic ester bonds, respectively.

Supercapacitance properties of porous carbon from chemical blending of phenolic resin and aliphatic dicarboxylic acids

Abstract

Preparation and characterization of novel thermostable polyamides bearing different photoactive pendent architectures with antibacterial properties

Three diamine monomers with different derivatives of imidazole heterocyclic ring, aryl ethers and electron withdrawing trifluoromethyl groups in the backbone were synthesized and used in polycodensation reaction with various aliphatic and aromatic dicarboxylic acids for preparation of a series of novel polyamides (PAs). The PAs were obtained in high yields and possessed inherent viscosities in the range of 0.26-0.75 dL/g. All of the polymers were amorphous in nature, showed outstanding solubility and could be easily dissolved in amide-type polar aprotic solvents. They showed good thermal stability with glass transition temperatures between 162-302 °C. Thermogravimetric analysis showed that all polymers were stable, with 10% weight loss recorded above 421 °C in N2 atmospheres. All the PAs presented fluorescence upon irradiation with ultraviolet light and thus showed promise for applications in electroluminescent devices. The monomers and PAs were also screened for antibacterial activity against Gram positive and Gram negative bacteria.