Synthesis and characterization of new soluble cardo polyesters derived from 1,1‐bis‐[4‐(4‐chlorocarboxyphenoxy)phenyl]‐4‐tert‐butylcyclohexane with various bisphenols by solution polycondensation

A new cardo diacid chloride, 1,1‐bis‐[4‐(4‐chlorocarboxyphenoxy)phenyl]‐4‐tert‐butylcyclohexane ( 4 ), was synthesized from 1,1‐bis‐[4‐(4‐carboxyphenoxy)phenyl]‐4‐tert‐butylcyclohexane in refluxing thionyl chloride. Subsequently, various new polyesters were prepared from 4 with various bisphenols by solution polycondensation in nitrobenzene using pyridine as a hydrogen chloride quencher at 150 °C. These polyesters were produced with inherent viscosities of 0.32–0.50 dL · g^?1. Most of these polyesters exhibited excellent solubility in a variety of solvents such as N,N‐dimethylformamide, tetrahydrofuran, tetrachloroethane, dimethyl sulfoxide, N,N‐dimethylacetamide, N‐methyl‐2‐pyrrolidinone, m‐cresol, o‐chlorophenol, and chloroform. These polymers showed glass‐transition temperatures (T_g's) between 144 and 197 °C. The polymer containing the adamantane group exhibited the highest T_g value. The 10% weight loss temperatures of the polyesters, measured by thermogravimetric analysis, were found to be in the range of 426–451 °C in nitrogen. These cardo polyesters exhibited higher T_g's and better solubility than bisphenol A‐based polyesters. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 2951–2956, 2001     

Synthesis and characterization of new aromatic polyesters containing cardo decahydronaphthalene groups

Three cardo bisphenols containing decahydronaphthalene group viz., 4,4′-(octahydro-2(1H)-naphthylidene)bisphenol, 4,4′-(octahydro-2(1H)-naphthylidene)bis-3-methylphenol and 4,4′-(octahydro-2(1H)-naphthylidene)bis-3,5-dimethylphenol were synthesized starting from commercially available 2-naphthol and were utilized for synthesis of new aromatic polyesters by phase transfer-catalyzed interfacial polycondensation with isophthaloyl chloride, terephthaloyl chloride and a mixture of isophthaloyl chloride and terephthaloyl chloride (50:50 mol %). Inherent viscosities and number average molecular weights (M_n) of polyesters were in the range 0.35-0.84 dL/g and 13,300-48,500 (Gel Permeation Chromatography, polystyrene standard), respectively. Polyesters were readily soluble in organic solvents such as dichloromethane, chloroform, tetrahydrofuran, meta-cresol, pyridine, N,N-dimethylformamide, N,N-dimethylacetamide, and 1-methyl-2-pyrrolidinone at room temperature and could be cast into tough, transparent and flexible films from their chloroform solutions. Wide-angle X-ray diffraction measurements revealed the amorphous nature of polyesters. The glass transition temperature of polyesters was in the range 207-287 °C. The temperature at 10% weight loss (T₁₀), determined from thermogravimetric analysis of polyesters, was in the range 425-460 °C indicating their good thermal stability.     

Synthesis and properties of new polyesters having tetrahydrofuran rings in their main chains

New polyesters 6a–6c consisting of 2,4-linked tetrahydrofuran rings were synthesized by bulk polycondensation of methyl trans- and cis-4-hydroxytetrahydrofuran-2-carboxylates ( 5a and 5b ) and a stereoisomeric mixture of methyl 4-hydroxy-5-methyltetrahydrofuran-2-carboxylate ( 5c ) at high temperature. These monomers were prepared from methyl glycolate or methyl lactate and diethyl maleate through a four-step reaction sequence. The polycondensation was carried out without solvent at different temperatures ranging from 150 to 220°C. Titanium isopropoxide was most effective among the catalysts examined, giving polyesters with number-average molecular weights up to 2 × 10⁴. Polyester 6a consisting of trans-2,4-linked tetrahydrofuran rings was soluble in trifluoroacetic acid and a mixed solvent of chloroform and methanol (10/1, v/v). Polyester 6b composed of cis-2,4-linked tetrahydrofuran rings was soluble in dimethyl sulfoxide and dimethylformamide in addition to the two solvents for 6a . Polyester 6c with 5-methyl-substituted tetrahydrofuran rings was composed of a mixture of stereoisomeric units and thus was soluble in a variety of solvents including chloroform, tetrahydrofuran, acetonitrile, dimethyl sulfoxide, and dimethylformamide. The glass transition temperatures of 6a, 6b , and 6c determined by DSC were 109, 88, and 66°C. These polyesters were found to be very slowly hydrolyzed in a neutral phosphate buffer solution at ambient temperature. © 1993 John Wiley & Sons, Inc.     

The oxidative coupling of indole with some phenolic compounds,naphthols and catechols

The oxidative coupling of indole with three naphthols, 2-naphthol, 2,3-dihydroxynaphthalene and 2,7-dihydroxynaphthalene gave 1,1-bis(3′-indolyl)-2(1H)naphthalenone, 1,1-bis(3′-indolyl)-3-hydroxy-2(1H)naphthalenone and 1,1-bis(3′-indolyl)-7-hydroxy-2(1H)naphthalenone, respectively. The coupling of indole with protocatechuic aldehyde gave bis-(3-indolyl)-(3′,4′-di-hydroxyphenyl)methane and that of indole with homocatechol gave 3-(2′-methyl-3′,4′-di-hydroxyphenyl)indole.     

Preparation and properties of fluorine-containing polyarylates from tetrafluoroisophthaloyl chloride and bisphenols

Fluorine-containing polyarylates having inherent viscosities of 0.2–0.8 dL/g were prepared from tetrafluoroisophthaloyl chloride and various bisphenols by low temperature solution polycondensation in chloroform with triethylamine or by two-phase polycondensation in a dichloromethane-water or nitrobenzene-water system with benzyltriethylammonium chloride as the phase transfer catalyst. These polyarylates were amorphous and were readily soluble in various solvents, including chloroform and N-methyl-2-pyrrolidone. The glass transition temperature of the polymer derived from 2,2-bis(4-hydroxyphenyl) propane was 150°C. These polyarylates started to lose weight around 350°C in an air or nitrogen atmosphere.     

Direct polycondensation of aromatic dicarboxylic acids and bisphenols with tosyl chloride and N,N-dimethylformamide in pyridine

A Vilsmeier adduct derived from arylsulfonyl chlorides and DMF in pyridine was successfully used as a new condensating agent for the synthesis of aromatic polyesters by the direct polycondensation of aromatic dicarboxylic acids and bisphenols and also of hydroxybenzoic acids. Polymers of high molecular weights (M?_w = 78,000) with relatively narrow molecular weight distribution (M?_w/M?_n ≈ 3.0) were prepared by reacting aromatic dicarboxylic acids with the adduct in pyridine, followed by addition of bisphenols. The polycondensation was significantly affected by the amount of DMF, the nature of the arylsulfonyl chlorides, the conditions of initial reaction of the acids with the adduct, and the rate of reaction with bisphenols. The process was adaptable to the direct polycondensation of hydroxybenzoic acids, affording polymers of high molecular weight (η_inh = 1.73).     

Preparation and steric structure of 2-Alkoxy-2,5-dioxo-4,4-bis(trifluoromethyl)-7(8)-chloro-1,3,2λ5-benzodioxaphosphepins

The reaction of hexafluoroacetone with 2-alkoxy-6(7)-chloro-1,3,2-benzodioxaphosphorin-4-ones yielded 7-and 8-chloro-substituted 2-alkoxy-2,5-dioxo-4,4-bis(trifluoromethyl)-1,3,2λ⁵-benzodioxaphosphepines. Their steric structure was studied by single-crystal X-ray diffraction. The effect of fluorinated substituents on the crystal packing of the benzophosphepines was demonstrated. Hydrolysis of these compounds gave the corresponding 4-and 5-chloro-substituted 2-(2-hydroxyphenyl)-2-oxo-1,1-bis(trifluoromethyl)-ethanols; the structure of 2-(2-hydroxy-5-chlorophenyl)-2-oxo-1,1-bis(trifluoromethyl)ethanol was also proved by single-crystal X-ray diffraction.     

Synthesis of a novel naphthalene-based poly(arylene ether-ketone) by polycondensation of 1,5-bis(4-fluorobenzoyl)-2,6-dimethylnaphthalene with bisphenol a

Synthesis of 1,5-bis(4-fluorobenzoyl)-2,6-dimethylnaphthalene ( 1 ), polycondensation of 1 with Bisphenol A, and properties of the obtained polymer were studied. Friedel–Crafts acylation of 2,6-dimethylnaphthalene with 4-fluorobenzoyl chloride in nitrobenzene selectivity afforded 1 in 82% yield. X-ray single crystal structural analysis of 1 confirmed that the dibenzoylation proceeded regioselectively and two methyl groups sterically inhibited the coplanarity of the two aromatic planes. The polycondensation of 1 with Bisphenol A in toluene/N-methyl-2-pyrrolidone (NMP) mixed solvent in the presence of excess potassium carbonate as a condensation reagent was carried out at 180°C for 4 h to quantitatively afford the corresponding poly(arylene ether-ketone) (PEK) 3 with high molecular weight (M?_n～30,000) as a slightly yellow powder. As the reaction time was prolonged, both M?_n and MWD of 3 increased and the solubility of 3 in chloroform clearly decreased. By GPC-LALLS, M?_n of 3 obtained by the polycondensation for 16 h, was 85,000. The PEK 3 with high molecular weight was produced in a quantitative yield in a variety of solvents such as sulfolane. Water formed during the polycondensation hardly affected the yield and molecular weight of 3 , although a small molecular weight decrease took place. To evaluate the special effect of the methyl groups of 3 , polycondensation of 2,6-bis(4-fluorobenzoyl)naphthalene 2 with bisphenol A was carried out for comparison and the corresponding PEK 4 was quantitatively obtained. Whereas 3 was soluble in ordinary organic solvents such as tet-rahydrofuran (THF), chloroform, and NMP at room temperature, 4 was insoluble in most solvents except for strong acids such as conc. sulfonic acid. The polymer 3 showed high glass transition temperature (238°C) and 5% weight loss temperature (457°C). Casting of the polymer from THF solution gave a transparent, tough, flexible, and amorphous film. © 1995 John Wiley & Sons, Inc.     

Five-membred 2,3-dioxoheterocycles: LXXXI. Reactions of 4,5-bis(methoxycarbonyl)-1H-pyrrole-2,3-diones with N-substituted 3-amino-5,5-dimethyl-2-cyclohex-2-en-1-ones. crystal and molecular structure of methyl 4′-hydroxy-6,6-dimethyl-1,1′-bis(4-methylphenyl)-2,4,5′-trioxo-1,1′,2,4,5,5′,6,7-octahydrospiro[indole-3,2′-pyrrole]-3′-carboxylate

1-Aryl-4,5-bis(methoxycarbonyl)-1H-pyrrole-2,3-diones react with N-substituted 3-amino-5,5-dimethylcyclohex-2-en-1-ones affording methyl 1,1′-diaryl-4′-hydroxy-6,6-dimethyl-2,4,5′-trioxo-1,1′,2,4,5,5′,6,7-octahydrospiro[indole-3,2′-pyrrole]-3′-carboxylates whose structure was proved by XRD analysis.     

Synthesis of new polycarbonate-polysiloxanes based on oligomeric organosilicon bisphenols

New linear polycarbonate-polysiloxanes are synthesized through the heterophase polycondensation of α,ω-bis[3-(4-hydroxy-3-methoxyphenyl)propyl]oligoorganosiloxanes (P_Si-bisphenols) with α,ω-bis(chloroformato)oligocarbonates (method I), the phosgenation of P_Si-bisphenol-diphenylolpropane mixtures (method II), the interaction of the same bisphenols with bis(4-chloroformatophenyl)propane (method III), and the polycondensation of the latter with P_Si-bisphenol-α,ω-dihydroxyoligocarbonate mixtures (method IV). The highest molecular masses (as high as 130 × 10³ at a degree of multiblockiness of 11–14 block pairs) are inherent in poly-carbonate-polysiloxanes synthesized by methods II and III; moreover, the same copolymers have the highest mechanical characteristics (σ_br and ?_br are as high as 48 MPa and 300%, respectively).     

Phenoxasilin-containing polyamides and polyesters

Silicon-containing polyamides and polyesters of a new type have been synthesized. They contain phenoxasilin rings with double-stranded structure. The polymers were synthesized by the interfacial polycondensation of 2,8-dichloroformyl-10,10-diphenylphenoxasilin with diamines and bisphenols, and were obtained in nearly quantitative yields. Their reduced viscosities were in the range of 0.53–1.47 dl g^?1 m dimethylformamide (DMF), m-cresol or chloroform. Some of the polyamides were soluble in polar aprotic solvents such as DMF and N-methyl-2-pyrrolidone (NMP) and the polyesters had good solubility in chloroform, phenol-sym tetrachloroethane (60:40 by wt %) and acidic solvents (m-cresol and nitrobenzene). The polymers hardly dissolved in cone. H₂SO₄ and some of them coloured in it. Only the polyester having sulphide bonds was soluble in benzene in addition to the above organic solvents. These polymers hardly degraded below 400° except for the polyamides derived from aliphatic diamines. The polymers from aliphatic diamines melted at 290–325°; the other polyamides and the polyesters decomposed without melting.     

Polyphenolic components of knotwood extracts from Abies sibirica

An extract from the knotwood of Abies sibirica (Siberian fir) was studied by HPLC, NMR spectroscopy, and mass spectrometry with the goal to identify new sources of phytoestrogens, which are promising medicinal agents, and to obtain new representatives of natural compounds of the indicated group. The following compounds were found in the extract and identified: 2-(4-hydroxy-3-methoxyphenyl)-3-hydroxymethyl-4-[1-hydroxy-1-(4-hydroxy-3-methoxy-phenyl)methyl]tetrahydrofuran (1), 5′-(7-hydroxymatairesinyl)-5″-(7?-hydroxymatairesinol) (2), 2,3-bis(4-hydroxy-3-methoxybenzyl)butane-1,4-diol (3, (?)-secoisolariciresinol), and 3-(4-hydroxy-3-methoxybenzyl)-5-(4-hydroxy-3-methoxyphenyl)-4-(hydroxymethyl)dihydro-furan-2(3H)-one (4). Compound 2 was previously unknown.

     

Linear polyesters containing isocyanurate rings

Two series of linear polyesters containing isocyanurate rings have been prepared to determine the effect of structural variations on thermal and solubility properties. The polyesters were prepared by the polycondensation reaction of isocyanurate containing difunctional acid and ester monomers with linear diols. The substituent on the isocyanurate ring and the length of the acid side chain have been shown to have considerable effect on the glass transition temperature T_g. Different solubility properties were observed for the series of polyesters in which the pendant substituent was ? C₆H₅ and the acid side-chain was ? CH₂CO₂H. These polymers were insoluble in THF, and the polyester prepared from 1,6-hexanediol was also insoluble in chloroform. Thermal gravimetric analysis (TGA) indicated that structural differences had no significant effect on the thermal stability of these linear polyesters.     

Synthesis and structures of 4,5-dimethyl-1,3-bis(pyridin-2-ylmethyl)-1H-imidazolium chloride and 1,1′-bis(pyridin-2-ylmethyl)-2,2′-bis(4,5-dimethylimidazole)

4,5-Dimethyl-1,3-bis(pyridin-2-ylmethyl)-1H-imidazolium chloride (1) was synthesized and characterized by IR and NMR spectroscopy and X-ray diffraction. An attempt to prepare the free tridentate N-heterocyclic carbene pincer ligand by the reaction of 1 with KN(SiMe₃)₂ resulted in the formation of 1,1′-bis(pyridin-2-ylmethyl)-2,2′-bis(4,5-dimethylimidazole) as a product of dimerization of the target carbene followed by the rearrangement accompanied by the elimination of dipyridylethane.

     

Phenazasiline-containing polyamides and polyesters

A Phenazasiline ring was incorporated into a polymer backbone by polycondensation of 2,8-dichloroformyl-5,10-dihydro-5-methyl-10,10-diphenylphenazasiline (V) with aromatic diamines or bisphenols, and phenazasiline-containing polyamides and polyesters were obtained. The polyamides were prepared by low-temperature solution polycondensation in N-methyl-2-pyrrolidone (NMP) in the presence of lithium chloride. The polyesters were synthesized by interfacial polycondensation in a mixture of 1,2-dichloroethane and aqueous alkali in the presence of tetrabutylammonium chloride as an accelerator. These reaction conditions gave the corresponding polymers with high viscosities. The phenazasiline-containing polyamides exhibited good solubilities in polar aprotic solvents such as dimethylformamide, dimethylacetamide, and NMP, and also in m-cresol, although the polyesters showed limited solubilities in organic solvents. Under nitrogen, the phenazasiline-containing polyamides and polyesters showed little degradation below 400°C and had good heat resistance.     

Synthesis of 4-β-D-arabinofuranosyl-5,6-dihydro-2H-1,2,4-thiadiazin-3-one 1,1-dioxide and x-ray diffraction analysis of its 2′,3-anhydro precursor

Reaction of 2-amino-3′,5′-bis(O-tert-butyldimethylsilyl)-β- D -arabinofuran[1′,2′:4,5]-2-oxazoline with 2-chloroethylsulfonyl chloride in the presence of sodium bicarbonate followed by removal of the protecting groups gave 2′,3-anhydro-4-β- D -arabinofuranosyl-5,6-dihydro-2H-1,2,4-thiadiazin-3-one 1,1-dioxide ( 5 ), which by treatment with ammonia was converted to 4-β- D -arabinofuranosyl-5,6-dihydro-2H-1,2,4-thiadiazin-3-one 1,1-dioxide ( 6 ). The structure of compound 5 was unequivocally established by means of an x-ray diffraction analysis. The compound crystallized in the space group P2₁2₁2₁ with unit cell dimensions a = 5.883(3), b = 9.352(2), c = 18.769(7) Å, Z = 4. Its structure was established by direct multisolution techniques and refined by the full matrix least squares method to a final R value of 0.058 for the 1515 reflections observed.     

Reformatsky Reaction of Methyl 1-Bromocycloalkanecarboxylates with α-Dicarbonyl Compounds

Reformatsky reactions of methyl 1-bromocyclohexanecarboxylate and methyl 1-bromocyclo-pentanecarboxylate with 2-aryl-2-oxoacetaldehydes involve both carbonyl groups of the latter and result in formation of 3a-aryl-3,3 : 6,6-bis(pentamethylene)- and 3a-aryl-3,3 : 6,6-bis(tetramethylene)tetrahydrofuro-[3,2-b]furan-2,5-diones. The reaction with 2-(2,4-dimethylphenyl)-2-oxoacetaldehyde gives acyclic products, methyl 1-[1-hydroxy-2-(2,4-dimethylphenyl)-2-oxoethyl]cyclohexanecarboxylate and methyl 1-[1-hydroxy-2-(2,4-dimethylphenyl)-2-oxoethyl]cyclopentanecarboxylate, while with benzil methyl 1-(4-hydroxy-1-oxo-3,4-diphenyl-2-oxaspiro[4.5]dec-3-yl)cyclohexanecarboxylate and methyl 1-(4-hydroxy-1-oxo-3,4-diphenyl-2-oxaspiro[4.4]non-3-yl)cyclopentanecarboxylate are obtained.     

Phenothiaphosphine-containing polyamides and polyesters

Phosphorus-containing polyamides and polyesters, which had tricyclic fused rings (phenothia-phosphine rings) in the main chain, were prepared and the properties of the resulting polymers were examined. These polymers were obtained at highly reduced viscosities in satisfactory yields by the polycondensation of 2,8-dichloroformyl-10-phenylphenothiaphosphine 5,5,10-trioxide with aromatic diamines or bisphenols. The polyamides and polyesters were soluble in polar aprotic solvents such as dimethylacetamide and N-methyl-2-pyrrolidone; the polyesters were also soluble in chloroform. The polymers exhibited good heat resistance. The phenothiaphosphine-containing polyamides and polyesters self-extinguished immediately when flame was removed and were highly flame-resistant. The polyester obtained from bisphenol A showed a limiting oxygen index value of 43.5.     

Synthesis of aromatic polythers by Scholl reaction. IV. Homopolymerization and copolymerization of α,ω-bis[4-(1-napthoxy)phenylsulfonyl]perfluoroalkanes

Polyether sulfones containing perfluoroalkyl segments were prepared by room temperature radical-cation polymerization (Scholl reaction) of 1,4-bis[4-(1-napthoxy)phenylsulfonyl]perfluorobutane ( 1a ) and 1,8-bis [4-(1-napthoxy) phenylsulfonyl] perfluoroctane ( 1b ) in nitrobenzene, using anhydrous ferric chloride as oxident. The homopolymerization of 1a and of 1b performed under various polymerization conditions, resulted in polymers with number average molecular weight (M?_n) up to 33,000 and 38,000 g/mol, respectively. Copolymerization of the fluorinated monomers 1a with 1b , and either 1a or 1b with 4,4′-bis(1-naphthoxy) diphenyl sulfone ( 4 ) and 1,5-bis (1-naphthoxy) pentane ( 5 ) produced copolymers of M?_n up to 18,100 g/mol. The reactivity of the various monomers was discussed on the basis of the induction and resonance stabilization effects.     

Crosslinked polymers containing adamantane groups

Diglycidyl ethers of 1,3-bis-(p-hydroxyphenyl)adamantane (BHPA) and 3,3'-bis-(p-hydroxyphenyl)-1,1'-biadamantane (BHPBA) were prepared and condensed with m-phenylenediamine and methyl tetrahydrophthalic anhydride to give polymers with good high temperature mechanical properties and good oxidative stability. These bisphenols were also condensed with formaldehyde to give phenolic resins containing adamantane moieties.