Aromatic Acid Chlorides Research Articles

New synthetic method for aromatic polyketones from bis(arylsilane)s and aromatic dicarboxylic acid chlorides

AbstractA new synthetic method for aromatic polyketones was developed through Friedel–Crafts polycondensation of bis(arylsilane) monomers with aromatic dicarboxylic acid chlorides. The solution polycondensation of these monomer pairs in the presence of aluminum chloride in 1,2‐dichloroethane readily afforded aromatic polyketones having inherent viscosities up to 0.37 dL/g with the elimination of chlorotrimethylsilane. The polycondensation proceeded through aromatic electrophilic ipso substitution, the mechanism of which is very similar to that of normal Friedel–Crafts acylation. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2729–2735, 2002

Synthesis and properties of new aromatic poly‐(ether benzoxazole)s from 2,2′‐bis(4‐amino‐3‐hydroxyphenoxy)biphenyl and aromatic dicarboxylic acid chlorides

AbstractA new bis(o‐aminophenol) with a crank and twisted noncoplanar structure and ether linkages, 2,2′‐bis(4‐amino‐3‐hydroxyphenoxy)biphenyl, was synthesized by the reaction of 2‐benzyloxy‐4‐fluoronitrobenzene with biphenyl‐2,2′‐diol, followed by reduction. Biphenyl‐2,2′‐diyl‐containing aromatic poly(ether benzoxazole)s with inherent viscosities of 0.52–1.01 dL/g were obtained by a conventional two‐step procedure involving the polycondensation of the bis(o‐aminophenol) monomer with various aromatic dicarboxylic acid chlorides, yielding precursor poly(ether o‐hydroxyamide)s, and subsequent thermal cyclodehydration. These new aromatic poly(ether benzoxazole)s were soluble in methanesulfonic acid, and some of them dissolved in m‐cresol. The aromatic poly(ether benzoxazole)s had glass‐transition temperatures of 190–251 °C and were stable up to 380 °C in nitrogen, with 10% weight losses being recorded above 520 °C. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2656–2662, 2002

Benzazoles. 1. Acylation of Benzothiazolin-2-ones by Aromatic Acid Chlorides Using Small Amounts of Zinc Chloride

We show that the yield of 6-aroylbenzothiazolin-2-ones, products of acylation of benzothiazolin-2-ones by aromatic acid chlorides in the presence of ZnCl2, depends on the degree of nucleophilicity of benzothiazolin-2-ones.

Solid-phase directed ortho-lithiation and the preparation of a phthalide library.

An efficient solid-phase synthesis of phthalides is described in which aromatic carboxylic acids or acid chlorides and ketones are used as building blocks. The carboxylic acid or acid chloride is tethered to aminomethylated polystyrene resin, forming a secondary amide, which functions as both the linker and the directing metalation group. This allows the resin-bound benzamides to be ortho-lithiated at 0 degrees C. The ortho-lithiated species can be quenched with benzaldehydes, benzophenones, and even acetophenones, affording resin-bound alcohols. A cyclative cleavage is induced by simply warming the resin in toluene or dioxane, yielding the desired phthalide compounds in exceptionally high purity.

Synthesis and Antioxidative Activity of Thio Esters Derived from ω-(3,5-Di-tert-butyl-4-hydroxyphenyl)alkanethiols

ω-(3,5-Di-tert-butyl-4-hydroxyphenyl)alkanethiols were converted into thio esters by reactions with aliphatic and aromatic carboxylic acid chlorides. The antioxidative activity of these compounds, evaluated with respect to thermal autooxidation of lard, was studied in relation to their structure.

Synthesis and Solution Properties of Deferoxamine Amides

The poor membrane permeability and oral bioavailability of the iron chelating agent deferoxamine (DFO) mesylate result from the low octanol/water partition coefficient and high aqueous solubility. With the ultimate aim to improve biomembrane permeability while retaining the iron‐binding ability of DFO, a series of more lipophilic amides were prepared by reacting the terminal primary amino group with fatty and aromatic acid chlorides or anhydrides. Octanol/water partition coefficients and equilibrium solubilities of these analogs in solvents, chosen to delineate physicochemical interactions, were determined as a function of temperature. Solid‐state properties were evaluated by calorimetry. All DFO amide derivatives had higher melting points, indicating that derivatives formed strong intermolecular interactions in the solid phase. Formamidation of the primary amine of deferoxamine resulted in a 200‐fold increase in the octanol/water partition coefficient and reduced aqueous solubility at least 2000‐fold compared with the parent molecule. The partition coefficient increased and aqueous solubility decreased 2‐fold with the addition of each methylene group in the homologous series of aliphatic amides. Solubilities of the derivatives in water‐saturated octanol and hexane showed irregular profiles as a function of increasing aliphatic chain length that were attributed to intermolecular packing in the solid state. The temperature dependence of the partition coefficients was interpreted to indicate that interfacial transfer of the deferoxamine amides was, in part, affected by an apparent diminished ability to form energetically favorable interactions in the water‐saturated organic phase. © 2000 Wiley‐Liss, Inc. and the American Pharmaceutical Association J Pharm Sci 89:1525–1536, 2000

Synthesis of aromatic polybenzoxazoles by silylation method and their thermal and mechanical properties

Various aromatic polybenzoxazole (PBO) films were prepared through the two-step silylation method by low-temperature solution polycondensation of trimethylsilyl-substituted bis(α-aminophenol)s with aromatic dicarboxylic acid chlorides yielding precursor poly(α-trimethylsiloxy-amide)s, followed by thermal cyclocondensation. Four aromatic PBOs had glass transition temperatures (T g ) in the range of 275-375°C, and the T g values were slightly lower than those of the structurally related polyimides. The temperatures of 10% weight loss of these PBOs ranged from 545-616°C in nitrogen, and the values were somewhat higher than those of the structurally similar polyimides. The films of the PBOs had tensile strengths of 105-135 MPa, elongations at break of 11-25%, and tensile moduli of 2.1-2.8 GPa.

Acylation of 1-arylpyrazolidin-3-ones

Acylation of 1-arylpyrazolidin-3-ones using aromatic acid anhydrides and chlorides in the presence of base occurs principally at the oxygen atom to give 1-aryl-3-acyloxy-2-pyrazolines, subsequent heating or microwave irradiation of which leads to the corresponding N-acylpyrazolidin-3-ones. The action of aliphatic acid anhydrides and chlorides on 1-arylpyrazolidin-3-ones gives predominantly the N-acylpyrazolidin-3-ones.

Electrochemical carboxylation of acyl chlorides, freons, and halogen-containing polymers

Processes of the carbon dioxide fixation are studied. The fixation is done by an electrochemical carboxylation of chlorides of aliphatic and aromatic carboxylic acids (acetyl chloride, benzoyl chloride and its derivatives), halogen-containing polymers (polyvinyl chloride, polyvinyl bromide), polybutadiene, and polyfluoroalkyl halides (CF3Br, CF3I, C3F7I). Major effects of some factors (reagent electronic structure, electrode materials, supporting electrolyte) on the occurrence of such processes and the yield of target products are studied.

Solvent and substituent effects in solvolyses of benzoyl chlorides. Variation of mechanisms from Grunwald–Winstein correlation analyses with YBnCl scales †

The solvolysis of seven aromatic acid chlorides, namely 2,6-dimethyl- (1), 2-methyl- (2), 4-methoxy- (3), 4-methyl- (4), 4-chloro-(6), 4-nitro- (7), and unsubstituted benzoyl chloride (5), in a variety of solvents was studied. The observation of a linear correlation of log k against solvent ionizing power YBnCl using the single-parameter Grunwald–Winstein equation indicates a limiting SN1 mechanism for the solvolysis of 1. An SN1 mechanism with significant nucleophilic solvent participation was found in the solvolysis of 2–4, based on the apparent splitting of lines in log kvs. YBnCl plots. Different types of non-SN1 reactions are probably involved in the solvolysis of 5–7, and are likely solvent dependent. Hammett-type plots against σ+ constants indicated a linear relationship for 3–6 only in solvents of high water content (60% aqueous methanol, 50% aqueous acetone and 50% aqueous ethanol) or with high ionising power (100% trifluoroethanol and 80% trifluoroethanol–20% ethanol), but for 3–5 in some solvents containing lower amounts of water or trifluoroethanol. Plots of log k in different solvents against ΔEiso for the isodesmic reaction also suggested a solvent dependence of mechanisms. The advantage of using YBnCl rather than a combination of YCl and aromatic ring parameter I in the correlation analysis is discussed.

N-Isocyanotriphenyliminophosphorane; a Convenient Reagent for the Conversion of Acyl Chlorides intoα-Diazoketones

Aliphatic, aromatic and vinylic acid chlorides were converted into the corresponding α-diazoketones in synthetically useful yields by reaction with N-isocyanotriphenyliminophosphorane followed by treatment of the resulting N-unsubstituted α-ketohydrazidoyl chlorides with triethylamine in the presence of a catalytic amount of p-toluenesulfonyl chloride.

Preparation and structure/property relationships of polyesters containing conjugated diacetylene groups

A series of novel polyesters containing conjugated diacetylenes (DA-polyesters) were prepared from various diacetylene diols with/without methyl side groups and isomers of aromatic acid chlorides via an interfacial condensation. A fully aliphatic DA-polyester was also prepared for comparison. All synthesised DA-polyesters are soluble in m-cresol, and the intrinsic viscosities were measured. In addition, compact and coherent films and sheets can be obtained from some of the polymers via solution or melt casting. The structure, morphology, and properties were characterized using spectroscopic methods, including FTIR, Raman, and WAXD and thermal analysis including TGA, DSC techniques. DMA was carried out on the solution-cast thin films and melt-processed samples. Close correlation was found between the structure and properties in these DA-polyesters. In particular, through analysis using isothermal DSC and Raman spectroscopy, the solid-state reactivity of the diacetylene groups in these polyesters was found related to the interchain spacings, which are, in turn, controlled by the molecular structure of the polymers. Results have shown that the aliphatic DA-polyester behaves very differently compared to the aromatic ones. Distinct differences were also observed among meta- and para-disubstituted isomers of the DA-polyesters. Furthermore, the introduction of methyl side groups has dramatically affected the thermal and thermal mechanical behavior by altering the interchain spacing of the polymers. © 1999 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 37: 965–974, 1999

Synthesis and thermal polymerization of aromatic 2-oxazolines containing carboxylic groups

2-(4-Carboxyphenyl)-1,3-oxazoline (2 a), 2-(3-carboxyphenyl)-1,3-oxazoline (2 b), and 2-(6-carboxynaphthyl-2-yl)-1,3-oxazoline (2 c) were synthesized by reaction of monomethyl ester chlorides of aromatic dicarboxylic acids with 2-chloroethylamine hydrochloride in the presence of triethylamine followed by cyclization with methanolic KOH. Thermal polymerization in bulk within a few minutes at 200–220°C resulted in new linear poly(ester amide)s 3 a–3 c without significant side reactions. The polymerization occurred in the melt phase (2 b) or in the solid state (2 a, 2 c) and the resulting polymers are amorphous (3 b) or semi-crystalline (3 a, 3 c). The polyaddition reactions were investigated by means of differential scanning calorimetry (DSC) and 1H NMR spectroscopy.

Synthesis and properties of phosphorus containing polyarylates derived from 2-(6-oxido-6H-dibenz 〈c,e〉〈1,2〉 oxaphosphorin-6-yl)-1,4-dihydroxy phenylene

A series of flame-retardant wholly aromatic polyesters was synthesized by high temperature solution polycondensation of 2-(6-oxido-6H-dibenz 〈c,e〉〈1,2〉 oxaphosphorin-6-yl)-1, 4-dihydroxy phenylene ( I) with various aromatic acid chlorides in o-dichlorobenzene. These polyesters have good mechanical properties (G’:10 8–10 9Pa) up to 180°C and good thermal and flame retardant properties. The glass transition temperatures of these polyesters are in the range of 198.1°C–220.3°C. The degradation temperatures ( T d 5%) in nitrogen ranged from 460°C to 495°C and char yields at 800°C are 34%–47%. The degradation temperatures ( T d 5%) in air ranged from 450°C to 472°C and char yields at 800°C are 21%–32%. The activation energies of degradation ranged from 177.4 KJ/mol to 238.8 KJ/mol. The limiting oxygen indexes (LOIs) of these polyesters are in the range of 37–48.

Synthesis and properties of phosphorus containing polyester-amides derived from 1,4-bis(3-aminobenzoyloxy)-2-(6-oxido-6H-dibenz?c,e??1,2?oxaphosphorin-6-yl) phenylene

A series of polyester-amides that contain phosphorus were synthesized by low temperature solution condensation of 1,4-bis(3-aminobenzoyloxy)-2-(6-oxido-6H-dibenz〈c,e〉〈1,2〉oxaphosphorin-6-yl) phenylene (III) with various aromatic acid chlorides in N-methyl pyrrolidone (NMP). All polyester-amides are amorphous and readily soluble in many organic solvents such as dimethylacetamide (DMAc), NMP, dimethylsulfoxide, and dimethylformamide at room temperature or on heating. Light yellow and flexible films of these polyester-amides could be cast from the DMAc solutions. The polymers with an inherent viscosity of 0.26–0.72 dL/g were obtained in quantitative yields. These polyester-amides have good mechanical properties (G′ of ∼ 109 Pa up to 200°C) and good thermal and flame retardant properties. The glass transition temperatures of these polyester-amides ranged from 250 to 273°C. The degradation temperatures (Td 5%) in nitrogen ranged from 466 to 478°C and the char yields at 800°C were 59.6–65.2%. The limiting oxygen indexes of these polyester-amides ranged from 35 to 43. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 891–899, 1999

Preparation and structure/property relationships of polyesters containing conjugated diacetylene groups

A series of novel polyesters containing conjugated diacetylenes (DA-polyesters) were prepared from various diacetylene diols with/without methyl side groups and isomers of aromatic acid chlorides via an interfacial condensation. A fully aliphatic DA-polyester was also prepared for comparison. All synthesised DA-polyesters are soluble in m-cresol, and the intrinsic viscosities were measured. In addition, compact and coherent films and sheets can be obtained from some of the polymers via solution or melt casting. The structure, morphology, and properties were characterized using spectroscopic methods, including FTIR, Raman, and WAXD and thermal analysis including TGA, DSC techniques. DMA was carried out on the solution-cast thin films and melt-processed samples. Close correlation was found between the structure and properties in these DA-polyesters. In particular, through analysis using isothermal DSC and Raman spectroscopy, the solid-state reactivity of the diacetylene groups in these polyesters was found related to the interchain spacings, which are, in turn, controlled by the molecular structure of the polymers. Results have shown that the aliphatic DA-polyester behaves very differently compared to the aromatic ones. Distinct differences were also observed among meta- and para-disubstituted isomers of the DA-polyesters. Furthermore, the introduction of methyl side groups has dramatically affected the thermal and thermal mechanical behavior by altering the interchain spacing of the polymers. © 1999 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 37: 965–974, 1999

Synthesis and Characterization of Novel Aromatic Polyamides from 1,4-Bis(4-aminophenyl)-2,3-diphenylnaphthalene and Aromatic Dicarboxylic Acids

A new highly phenylated diamine, 1,4-bis(4-aminophenyl)-2,3-diphenylnaphthalene, was synthesized in two steps starting from 2,5-bis(4-nitrophenyl)-3,4-diphenylcyclopentadienone. New aromatic polyamides containing tetraphenylnaphthalene unit were prepared by low temperature solution polycondensation of this diamine with various aromatic dicarboxylic acid chlorides. These polyamides had inherent viscosities of 0.45—0.82 dlg−1. Polyamides with m-phenylene moiety and flexible connecting group were soluble in various organic solvents such as N,N-dimethylacetamide and N-methyl-2-pyrrolidone, but those with rigid symmetric structures were soluble in only hot N,N-dimethylacetamide and N-methyl-2-pyrrolidone. The glass transition temperature of the polyamides ranged from 268 to 366°C, and the 10% weight loss temperatures were above 500°C in air.

Synthesis and properties of phosphorus-containing polyesters derived from 2-(6-oxido-6H-dibenz?c,e??1,2?oxaphosphorin-6-yl)-1,4- hydroxyethoxy phenylene

A series of phosphorous-containing aliphatic polyesters were synthesized by high-temperature solution condensation of 2-(6-oxido-6H-dibenz〈c,e〉〈1,2〉oxaphosphorin-6-yl)-1,4-hydroxyethoxy phenylene (III) with various aromatic acid chlorides in o-dichlorobenzene. All polyesters are amorphous and readily soluble in many organic solvents such as DMAc, NMP, DMSO, and o-dichlorobenzene at room temperature or upon heating. These polyesters are thermally quite stable. The glass transition temperatures of these aliphatic polyesters ranged from 126.6 to 162.2°C. The degradation temperatures (Td onset) in nitrogen ranged from 424 to 448°C, and the char yields at 700°C are 20–32%. The activation energies of degradation ranged from 160.9 to 226.0 kJ/mol. The LOIs of these polyesters ranged from 36 to 43. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 3051–3061, 1998

Synthesis and characterization of new aromatic polyesters and a polyether derived from 2,2-bis(4-hydroxyphenyl)-1,2-diphenylethanone

New polyarylates and aromatic polyethers were synthesized from 1,2-bis(4-hydroxyphenyl)-1,2-diphenylethylene, and aromatic dicarboxylic acid chlorides and aromatic dihalides, respectively. The polyarylates having inherent viscosities of 0.28–1.05 dL/g were synthesized by either the two-phase method or the high-temperature solution method. All the polymers were easily soluble in N-methyl-2-pyrrolidone, N,N-dimethylformamide, pyridine, m-cresol, 1,4-dioxane, and 1,1,2,2-tetrachloroethane. They have glass transition temperatures in the range of 217–250°C and showed no weight loss below 315°C in both air and nitrogen atmospheres. Aromatic polyethers with inherent viscosities of 0.85–1.21 dL/g were obtained by the polycondensation of 1,2-bis(4-hydroxyphenyl)-1,2-diphenylethylene and aromatic difluorides in the presence of potassium carbonate. These polymers having glass transion temperatures of 193–220°C were also soluble in the aforementioned solvents and stable up to around 350deg;C in both atmospheres. © 1994 John Wiley & Sons, Inc.

Synthesis and properties of new solubleN-phenyl-substituted aromatic-aliphatic and all aromatic polyamides derived from 4,4?-dianilinobiphenyl

New N-phenylated aromatic-aliphatic and all aromatic polyamides were prepared by the high-temperature solution polycondensation of 4,4′-dianilinobiphenyl with both aliphatic (methylene chain lengths of 6–11) and aromatic dicarboxylic acid chlorides. All of the aromatic-aliphatic polyamides and the wholly aromatic polyamides exhibited an amorphous nature and good solubility in amide-type and chlorinated hydrocarbon solvents, except for those aromatic polyamides containing p-oriented phenylene or biphenylylene linkages in the backbone; the latter were crystalline and insoluble in organic solvents except m-cresol. The N-phenylated aromatic-aliphatic polyamides and aromatic polyamides had glass transition temperatures in the range of 79–116°C and 207–255°C, respectively, and all the polymers were thermally stable with decomposition temperatures above 400°C in air. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2193–2200, 1998