Diacid Chlorides Research Articles

Synthesis, characterization and photo – switching properties of azobenzene mesogen containing poly (ether - ester) s from cashew nut shell liquid

Poly(ether - ester)s containing azobenzene mesogen were prepared from cardanol, a natural renewable resource and waste of the cashew industry. The azobenzene group containing cardanol (HPPP) was synthesized by the coupling reaction between diazotized aminophenol and cardanol. Further, it was alkylated with 3 – bromopropanol by Williamson’s etherification process to 3- {4- [4-(3- hydroxy propoxy) phenylazo] -3- pentadecyl phenoxy} propan – 1 – ol(3-HPPP). This dihydroxy compound was characterized by CHN analyzer, UV and 1H and 13C - NMR spectroscopies. A series of azobenzene mesogen containing poly (ether – ester)s were synthesized from 3-HPPP and various aliphatic and aromatic diacid chlorides by solution polycondensation technique. The molecular structure of the monomer and polymers was confirmed by FTIR, 1H and 13C - NMR spectral analyses. These polymers were studied for their thermal stability and photochemical properties. Thermal properties were evaluated by TGA and DSC. Hot-stage optical polarizing microscopy (HOPM) study showed that most of the polymers exhibit smectic and highly ordered band structure. The photo-switching property of azopolymers was investigated using UV – Vis spectroscopy and noticed that trans to cis isomerization occurs within 35 s in DMF, whereas reverse process takes place in 4 h in DMF solvent.

Biodegradable Aromatic–Aliphatic Poly(ester–amides) from Monolignol-Based Ester Dimers

Biobased polymers with tunable properties have received increased attention in the literature due to a decline in petroleum reserves. Owing to its low cost, abundance, and aromatic structure, lignin has great potential as a feedstock for value-added polymeric products. In this work, we condensed carboxylic acid precursors with monolignols to generate reactive dimers for polymer synthesis. Three different aromatic ester dimers, each corresponding to a different monolignol, were synthesized and characterized. The dicarboxylic acid dimers were converted to the corresponding diacid chloride in situ with thionyl chloride, and a series of poly(ester–amides) were synthesized via interfacial polymerization of these diacid chlorides with seven different aliphatic or aromatic diamines. The thermal properties (decomposition, glass transition temperature, and melting temperature) and hydrolytic stability in acidic and neutral aqueous conditions of the resulting polymers were studied.

Synthesis of phospholipidated β‐cyclodextrin and its application for flame‐retardant poly(lactic acid) with ammonium polyphosphate

ABSTRACTIn this study, phospholipidated β‐cyclodextrin (PCD) was obtained by the condensation between β‐cyclodextrin and phenyl phosphonic acid dichloride, which was characterized by Fourier transform infrared (FTIR) spectra, 1H‐NMR, and thermogravimetric analysis (TGA). The thermal stability and flame retardancy of the poly(lactic acid) (PLA) blends [PLA–ammonium polyphosphate (APP)–PCD] were measured by TGA coupled to FTIR spectroscopy, vertical burning test (UL‐94), limiting oxygen index (LOI), and cone calorimetry tests. The results show that the mass ratio and loading amount of APP and PCD affected the properties of PLA. When the loading of APP and PCD was 30 wt % and the mass ratio of APP to PCD was 5:1, the highest LOI value of 42.6% (that of neat PLA was 19.7%) and a UL‐94 V0 rating were achieved, and the reduction of the total heat release was greater than 80%. Even when the total amount of APP and PCD was decreased to 20 wt % with the same mass ratio, the flame‐retardant PLA still can achieved a UL‐94 V0 rating. The improved performance was explained by the formation of an intumescent, continuous, contact char layer. Moreover, the reaction between APP and PCD contributed to the improvement of the thermal stability of the char residue. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46054.

Synthesis and properties of semi-crystalline poly(decamethylene terephthalamide) thermosets from reactive side-group copolyamides

We have prepared semi-crystalline polyamide (PA) thermosets using reactive side-group functionalized copolyamides as precursors. Reactive meta- and para-based phenylethynyl diacid chlorides (IPE and TPE) were synthesized and incorporated in poly(decamethylene terephthalamide) (PA 10T) using a low temperature solution polymerization method. The phenylethynyl-based comonomers disrupt crystallization of the final copolyamides and lower the onset of melting. Copolyamides containing 5, 10 and 15 mol% of the reactive comonomer could be cured at 350 °C into freestanding PA thermoset films. All thermoset films are stable up to 400 °C, as confirmed by DMTA, which is the result of network formation. The thermosets exhibit both a crystalline phase and a crosslinked amorphous phase. Depending on the concentration of the side-groups, the degree of crystallinity of the final thermosets can be controlled and suppressed by 52–76% compared to the PA 10T reference polymer. Most notable is the fact that the IPE-15 thermoset film exhibits outstanding stress–strain behavior, i.e. elongation at break (∼17%) and toughness (766 MJ·m−3).

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.

Group IVB metallocene polyesters containing camphoric acid and preliminary cancer cell activity

ABSTRACTPolyesters were formed from the reaction of the salt of camphoric acid and Group IVB metallocene dichlorides using the interfacial polycondenzation process. The polyesters were formed in good yields with moderate chain lengths. Fourier transform infrared spectroscopy shows bands characteristic of the presence of both reactants with new bands characteristic of the formation of the M‒O and M–O(CO) linkage present. The polymers largely exist in a bridging geometry of the carbonyl groups about the metal atom. Nuclear magnetic resonance shows the presence of bands derived from both reactants. Matrix-assisted laser desorption/ionization mass spectroscopy shows ion fragments to three units for the polymers with isotopic abundance characteristic of the presence of metal atoms in the ion fragment clusters. All the polymers exhibit good ability to inhibit all the tested cancer cell lines but the zironocene and hafnocene polymers exhibit especially good inhibition of the tested cancer cell lines that included two pancreatic cancer cell lines. They represent a potential new group of anticancer drugs.

(E)-2-(1-Cyano-2-methoxy-2-oxoethylidene)-3,4-dioxo-1-(pyridin-1-ium-1-yl)cyclobutan-1-ide

(E)-2-(1-Cyano-2-methoxy-2-oxoethylidene)-3,4-dioxo-1-(pyridin-1-ium-1-yl)cyclobutan-1-ide was obtained by a three-component reaction of squaric acid dichloride with pyridine and methyl cyanoacetate.

Group IVB Metallocene Polyesters Containing Camphoric Acid and Preliminary Cancer Cell Activity

Polyesters were formed from the reaction of the salt of camphoric acid and Group IVB metallocene dichlorides employing the interfacial polycondensation process. The polyesters were formed in good yields with moderate chain lengths. FTIR shows bands characteristic of the presence of both reactants with new bands characteristic of the formation of the M-O and M-O(CO) linkage present. The polymers largely exist in a bridging geometry of the carbonyl-groups about the metal atom. NMR shows the presence of bands derived from both reactants. MALDI MS shows ion fragments to three units for the polymers with isotopic abundances characteristic of the presence of metal atoms in the ion fragment clusters. All of the polymers exhibit good ability to inhibit all of the tested cancer cell lines but the zironocene and hafnocene polymers exhibit especially good inhibition of the tested cancer cell lines that included two pancreatic cancer cell lines. They represent a potential new group of anticancer drugs.Polyesters were formed from camphoric acid and Group IVB metallocene dichlorides employing the interfacial polycondensation process. IR, NMR and MLADI MS results are consistent with the proposed structure. Polymers exhibit outstanding ability to inhibit the tested cancer cell lines including two pancreatic cancer cell lines. They represent a potential new group of anticancer drugs.

Lipophilic Polycation Vehicles Display High Plasmid DNA Delivery to Multiple Cell Types.

A class of cationic poly(alkylamidoamine)s (PAAAs) containing lipophilic methylene linkers were designed and examined as in vitro plasmid DNA (pDNA) delivery agents. The PAAAs were synthesized via step-growth polymerization between a diamine monomer and each of four different diacid chloride monomers with varying methylene linker lengths, including glutaryl chloride, adipoyl chloride, pimeloyl chloride, and suberoyl chloride, which served to systematically increase the lipophilicity of the polymers. The synthesized polymers successfully complexed with pDNA in reduced serum medium at N/P ratios of 5 and greater, resulting in polyplexes with hydrodynamic diameters of approximately 1 μm. These polyplexes were tested for in vitro transgene expression and cytotoxicity using HDFa (human dermal fibroblast), HeLa (human cervical carcinoma), HMEC (human mammary epithelial), and HUVEC (human umbilical vein endothelial) cells. Interestingly, select PAAA polyplex formulations were found to be more effective than Lipofectamine 2000 at promoting transgene expression (GFP) while maintaining comparable or higher cell viability. Transgene expression was highest in HeLa cells (∼90% for most formulations) and lowest in HDFa cells (up to ∼20%) as measured by GFP fluorescence. In addition, the cytotoxicity of PAAA polyplex formulations was significantly increased as the molecular weight, N/P ratio, and methylene linker length were increased. The PAAA vehicles developed herein provide a new delivery vehicle design strategy of displaying attributes of both polycations and lipids, which show promise as a tunable scaffold for refining the structure-activity-toxicity profiles for future genome editing studies.

PH-Triggered Release from Polyamide Microcapsules Prepared by Interfacial Polymerization of a Simple Diester Monomer.

The majority of current pH-triggered release systems is designed to respond to either low or high pH. Encapsulants based on polyampholytes are an example of materials that can respond to both acidic and basic pH. However, polyampholyte-based encapsulants generally possess a low loading capacity and have difficulty retaining their small-molecule cargo. The current work utilizes interfacial polymerization between polyamines and a pyromellitic diester diacid chloride to form high capacity "liquid core-shell" polyamide microcapsules that are stable in a dry or nonpolar environment but undergo steady, controlled release at pH 7.4 and accelerated release at pH 5 and pH 10. The rate of release can be tuned by adjusting the amine cross-linker feed ratio, which varies the degree of cross-linking in the polymer shell. The thin-shell microcapsule exhibited suitable barrier properties and tunable dual acid/base-triggered release, with applications in a wide range of pH environments.

Synthesis and characterization of photo-crosslinkable liquid crystalline copolyesters containing arylidene-keto and chalcone moieties

A series of six photo-crosslinkable thermotropic liquid crystalline copolyesters were prepared by polycondensation method at room temperature using tetra-n-butylammonium bromide as the phase transfer catalyst. The diacid chloride involved in this process was adipoyl chloride, the common diol (diol-1), also referred to as bischalcone diol, used was 3,3′-benzene-1,4-diylbis[1-(4-hydroxyphenyl)prop-2-en-1-one] and six different arylidene diols were involved as varying diols (diol-2), in the ratio 2:1:1. The common diol and the six arylidene diols were synthesized by the acid-catalyzed Claisen-Schmidt synthesis. The inherent viscosity ηinh of these six copolyesters was found between 0.35 and 0.45. The microstructure of the repeating unit present in the copolyester chain was confirmed by FT-IR, 1H–NMR and 13C–NMR spectroscopic techniques. Thermal transition temperatures, resolved from the DSC thermograms, were found to be well above room temperature. Optical polarizing microscopy was employed to establish the liquid crystalline property and all the polymers were found to have nematic phase. The photo-crosslinking behaviour of these copolyesters was studied in DMF solution at different time intervals. The copolyesters having methoxy group in them absorb UV-A rays (315–400 nm) for a longer duration, which promotes them to be good candidates for UV filters and sunscreens.

Stannathianes as activated polythiols for the synthesis of functionalized macrocyclic polythiolactones

We synthesized novel macrocyclic dithiolactones bearing endocyclic ether, polyether and lactone groups using new stannadithianes as tin templates in the condensation reaction with acid dichlorides and demonstrated an extension of this method toward synthesizing spirotetrathiolactones of controlled size. The structures of all synthesized compounds were characterized by spectroscopic methods.

Synthesis of Chiral Polyamides Containing an (R,R)‐1,2‐Diphenylethylenediamine Monosulfonamide Structure and Their Application to Asymmetric Transfer Hydrogenation Catalysis

AbstractA chiral main‐chain polyamide containing an (R,R)‐1,2‐diphenylethylenediamine monotoluenesulfonamide (TsDPEN) repeating unit was prepared. Polycondensation of dicarboxylic acid dichloride with the chiral bisaniline of N‐tert‐butoxycarbonyl‐protected TsDPEN was successful and afforded a chiral polyamide with a TsDPEN repeating unit as the chiral ligand structure. Treatment of the main‐chain polymer chiral ligand with transition‐metal complexes, such as [IrCl2Cp*]2 (Cp*=η5‐pentamethylcyclopentadienyl), [RhCl2Cp*]2, and [RuCl2(p‐cymene)]2, afforded polymer chiral metal complexes. Asymmetric transfer hydrogenation of a cyclic sulfonamide was efficiently catalyzed by the chiral TsDPEN polymer–metal complex to give an optically active cyclic sulfonylamine with quantitative conversion and high enantioselectivity. The polymer catalyst was easily recovered from the reaction mixture and reused several times without any loss in catalytic activity or enantioselectivity.

Ferrocene Based Azo Chromophore Functionalized Polyesters and Its Organic Analogue: Synthesis, Structural Elucidation, Thermal Behavior and IV Characterization

Azo-functionalized polyesters were synthesized via a low temperature solution polycondenstion of 4,4′-bis(4-azo-1-hydroxyphenyl)biphenyl methane (A) with four different diacid chlorides [terephthalyolchloride (T), isophthaloyl chloride (I), trans-azobenzene-4,4′-dicarbonyl chloride (TA) and ferrocenedicarboxylic acid chloride (Fe)]. The synthesized polymers were characterized by FTIR and 1HNMR spectrophotometric techniques and the structural property relation was studied in terms of solubility measurements, WAXRD, bleeding test, viscosities and UV/Visible spectroscopic analysis. Thermal properties were explored by means of thermogravimetric analysis and differential scanning calorimetry. LOI values, calculated by using the Van Krevelen–Hoftyzer equation were found in the range 35–37.8. Conductivity measurements showed that ferrocene based polymer were most conducting material with maximum conductivity 4.56 × 10−4 Scm−1. The material had relative viscosities in range 1.585–1.128 dL/g showing high molecular weights.

Design-Syntheses, Characterization and Biological Activity Studies of Azobenzen-P,Pꞌ-Di(3,1-Benzoxazin-4-One-2yl) and Azobenzen-P,Pꞌ-Di[(3- Substituted 3(4H)Quinazolinone-2yl] Derivatives

Sixteen azobenzene-p,pežŒ-di[3-substituted-4(3H)quinazolinone-2yl] were synthesized from reaction of azobenzenp, pežŒ-di(3,1-benzoaxzin-4-one-2yl) with amino-moieties nucleophlies, like hydrazinehydrate, hydroxylamine, p,toluidine, p-aminobenzene sulphonamide, 2-pyrimidine, 5-nitro-2-aminopyridine, ethyleneamine,5-(p-bromo) phenyl-2-aminothiazol, p,pežŒ-diamino diphenyl sulphone, quinidine hydrochloride, urea, thiourea, 3,5-dimethyl- 2-phenyl-4-aminopyrazolin-3-one, N(5-methyl-3-isoxazolyl)-p-aminobenzen sulphonamide, semicarbazide and thiosemicarbazide, in a molar ratio (1:2) respectively. azobenzen-p,pežŒ-di(3,1-benzoaxzin-4-one-2yl), was synthesized by following serial synthetic pathway. Reductive-condensation of p-nitrobenzoic acid in basic media give azobenzenp, pežŒ-dicarboxylic acid, then treated with thionyl chloride to give azobenzen-p,pežŒ-diacid chloride. It condensed with anthranilic acid to give azobenzen-p,pežŒ-[(dibenzoic acid-2yl)dicarboxamide], upon treatment with thionyl chloride give azobenzen-p,pežŒ-di(3,1-benzoaxzin-4-one-2yl). All synthesized compounds characterized by FTIR, 1HNMR, 13CNMR and mass spectral analyses. All synthesized azobenzen-p,pežŒ-di(3,1-benzoaxzin-4-one-2yl), and sixteen azobenzenep, pežŒ-di[3-substituted-4(3H)quinazolinone-2yl] compounds, were examined as antibacterial agents against gm(+ve and –ve) bacteria, and antifungal agents. Results showed abroad extended to moderate effects as antibacterial and antifungal agents.

New bio-based monomers: tuneable polyester properties using branched diols from biomass.

A family of monomers, including 2,5-hexandiol, 2,7-octandiol, 2,5-furandicarboxylic acid (FDCA), terephthalic acid (TA), and branched-chain adipic and pimelic acid derivatives, all find a common derivation in the biomass-derived platform molecule 5-(chloromethyl)furfural (CMF). The diol monomers, previously little known to polymer chemistry, have been combined with FDCA and TA derivatives to produce a range of novel polyesters. It is shown that the use of secondary diols leads to polymers with higher glass transition temperatures (Tg) than those prepared from their primary diol equivalents. Two methods of polymerisation were investigated, the first employing activation of the aromatic diacids via the corresponding diacid chlorides and the second using a transesterification procedure. Longer chain diols were found to be more reactive than the shorter chain alternatives, generally giving rise to higher molecular weight polymers, an effect shown to be most pronounced when using the transesterification route. Finally, novel diesters with high degrees of branching in their hydrocarbon chains are introduced as potential monomers for possible low surface energy materials applications.

Synthesis from (–)-α-Pinene of an Optically Active Macrocyclic Diesterdihydrazide with 2,6-Pyridinedicarboxylic and Adipic Acid Moities

An optically active macrocyclic diesterdihydrazide with 2,6-pyridinedicarboxylic and adipic acid moieties was synthesized efficiently from available (–)-α-pinene through an intermediate hydroxyketone [1R-(1′-hydroxyethyl)-3R-(2″-hydroxyethyl)-2,2-dimethylcyclobutane) using successive [2 + 1]-reaction of the last with 2,6-pyridinedicarboxylic acid dichloride and [1 + 1]-condensation of the resulting diketodiester with adipic acid dihydrazide.

Preparation and Properties of Soluble, Thermally Stable Poly(Silyl ether amide)s and Related Silica Nanocomposites

ABSTRACTSoluble poly(silyl ether amide)s and related nanocomposites with improved thermally stability was prepared. For this, a diamine was prepared through reaction of para-aminophenol with dichlorodiphenylsilane. Structure of diamine was confirmed with conventional spectroscopic methods. Poly(silyl ether amide)s was synthesized through polycondensation of diamine with different diacid chlorides. Properties of poly(silyl ether amide)s comprising thermal behavior, thermal stability, solubility, solution viscosity, and morphology were studied. Polymers showed high thermal stability and good solubility in organic solvents due to their unique structures. Related nanocomposites with different contents of silica nanoparticles (10–40 wt%) were prepared and their properties compared with pristine polyamides.

Multicomponent Coupling Approach to Cross-Conjugated Polymers from Vanillin-Based Monomers

We describe the use of vanillin-based monomers as a renewable feedstock for the synthesis of cross-conjugated polymers. This transformation exploits a catechyl-substituted phosphonite mediated multicomponent polymerization to convert vanillin-derived diimines, commercial diacid chlorides, and simple alkynes or alkenes into conjugated pyrrole-based polymers. The flexibility of the multicomponent polymerization has allowed for the efficient formation of families of vanillin-derived fluorescent polymers with tunable properties. This includes coupling vanillin with furan-based acid chlorides as the first cross-conjugated polymer composed of both components of lignocellulosic biomass.

Water clusters with anion templates in cucurbit[6]uril supramolecular pseudorotaxanes

Two types of anion water clusters have been observed in cucurbit[6]uril based pseudorotaxanes with two kinds of guests. (COO−)2(C2H5OH)2(H2O)4 anion water clusters and (H2O)2 water clusters are formed with the carboxylate groups of the guest 1, 1′-(hexane-1, 6-diyl) dipyridinium-4-carboxylate inner salt (HDPC) and connect the pseudorotaxane molecules to form 3D networks. Anion water clusters Cl2−(H2O) with independent water molecules are observed in the crystal structure of the pseudorotaxane with the guest 1, 1′-(hexane-1, 6-diyl) dipyridinium-4-hydroximic acid dichloride (HDHD). The results revealed that terminal groups of the guests, the solvents and the anions species in cucurbit Arunachalam and Ghosh (2011) uril pseudorotaxanes could affect the structures and the sizes of water clusters.