Cationic copolymerization of phenyl propenyl ethers

Ring-substituted phenyl propenyl ethers were found to form homopolymers without any rearrangement by metal halides. Phenyl propenyl ethers were less reactive than the corresponding phenyl vinyl ethers in cationic polymerization. In order to study the electronic effect of a substituent on the reactivity, cis-p-Cl,p-CH₃, and p-CH₃O-phenyl propenyl ethers were copolymerized with phenyl propenyl ether in methylene chloride at ?78°C with stannic chloride–trichloroacetic acid, and their ¹H- and ¹³C-NMR spectra were measured. The reaction constant ρ against Hammett σ_p was ?2.1. The cis-phenyl propenyl ethers were slightly more reactive than the corresponding trans isomers. On the other hand, an o-methyl group decreased the reactivity of phenyl propenyl ether. The low reactivity of o-methyl phenyl propenyl ether was attributed to the steric hindrance between the propagating carbocation and the monomer.     

A novel insertion reaction of epoxy compounds into phenyl ester linkages in polymer chains

The insertion reaction of various epoxy compounds such as phenyl glycidyl ether (PGE), methyl glycidyl ether, butyl glycidyl ether (BGE), and styrene oxide into the phenyl ester linkage in the polymer chain was investigated using quaternary ammonium salts as catalysts in diglyme, anisole, sulfolane, o-dichlorobenzene, or DMSO at 100–150°C. The reaction of PGE with poly[4-(4-nitrobenzoyloxy)styrene] (polymer 1a ) proceeded almost quantitatively to give the corresponding polymer using tetrabutylammonium bromide (TBAB) as catalyst in diglyme at 100°C for 24 h. The reactions of BGE with poly(4-nitrophenyl methacrylate), and copolyarylate derived from 2,2-bis(4-hydroxyphenyl)-1,1,1,3,3,3-hexafluoropropane and iso- and terephthaloyl chlorides also produced the corresponding polymers with 86 and 89 mol% new structural units, respectively, using TBAB in sulfolane at 150°C for 24 h. Furthermore, it was found that the degree of insertion of the epoxy compound into the ester linkage in the polymer chain was affected by the kind of epoxy compound, reaction solvent, catalyst concentration, substituent group on the phenyl ester, and structure of the polymer. Chiral polymers were also synthesized with high degrees of insertion by the reaction of chiral epoxides such as (R)-1,2-epoxyhexane, (R)-1,2-epoxyheptane, and (R)-1,2-epoxydecane with polymer 1a and poly(2,4-dichlorophenyl methacrylate) using TBAB in diglyme at 120°C for 24 h.     

Epoxy compounds. VIII. Stereoregular and stereorandom polymerization of phenyl glycidyl ether with tertiary amines,and infrared spectra of poly(phenyl glycidyl ether)

Crystalline and amorphous polymers have been obtained from the polymerization of phenyl glycidyl ether in the presence of tertiary amines. The crystalline fraction is high melting and insoluble at room temperature. The amorphous fractions are soluble at room temperature and their molecular weights are found to be ～950 in benzene at 30°C. The yields of the crystalline fraction and the amorphous paste fraction decreased considerably with increasing the catalyst concentration and reaction temperature above 50°C. The yield of the liquid fraction, however, increased with increasing concentration of the catalyst and the reaction temperature. The x-ray diffraction analysis of the crystalline fraction shows that the fraction has 47–50% crystallinity and that its diffraction pattern is similar to that of poly(phenyl glycidyl ether) obtained by Noshay and Price. The infrared spectra of these fractions have been obtained in the region of 650–4000 cm.^?1. These data are compared with those of polystyrene and poly(styrene oxide) and are used to make an assignment of the normal modes of the poly(phenyl glycidyl ether) molecule. On the basis of analyses of polystyrene and poly(styrene oxide), and a study of the combination bands, it has been possible to make a fairly satisfactory assignment of all of the benzene ring fundamentals of the CH₂, CH, and skeletal modes.     

The preparation of some 1-(2-furyl)-2-arylethylenes

Some 1-(2-furyl)-2-arylethylenes, where the furan nucleus is substituted in position 5 with a methyl or p-chlorophenyl group and where the aryl group is phenyl, p-nitrophenyl, α-naphthyl or β-naphthyl, have been prepared by the Perkin reaction and subsequent decarboxylation of the acid. The compounds 1-12 were prepared lor of photochemistry and photoelectron spectroscopy studies. Their geometrical configurations has been established by ¹H nmr and ir spectra.     

Enantioselective Hydrolysis of Glycidyl Methylphenyl Ethers by <Emphasis Type="Italic">Botryosphaeria Dothidea</Emphasis> ZJUZQ007: Effect of Substitution Pattern on Enantioselectivity

Resolution of racemic glycidyl (o, m, p)-methylphenyl ethers by using a newly isolated Botryosphaeria dothidea ZJUZQ007 with epoxide hydrolase activity affords enantiopure epoxides with enantiomeric excesses (e.e._s) of 91–99% and enantiomeric ratios (E) of 18.1 to 48.6. The (R)-enantiomer was obtained from rac-glycidyl (o or m)-methylphenyl ethers whereas the (S)-epoxides was obtained from glycidyl p-methylphenyl ether. Substitution pattern of the methyl group exerted effects both on configurations of the remaining epoxides and enantioselectivities of epoxide hydrolase. The observations were explained by enzyme-substrate docking studies. It is the first example showing that for kinetic resolution of glycidyl methylphenyl ethers, fungal species of B. dothidea was applied.     

Copolymerization of some epoxides by coordination-type catalysts

Copolymerizations of tritiated phenyl glycidyl ether with p- and m-methoxy, p-methyl, and p-chloro analogs, as well as with propylene oxide and epichlorohydrin are reported. The relative reactivities indicate greater Lewis acid character for triethylaluminum–water than for diethyl-zinc–water or ferric chloride–propylene oxide catalyst systems. The copolymerization of the PGE analogs is promoted by electron-donor groups and retarded by electron-withdrawing groups.     

Determination of phosphatidylcitoline in serum with use of a choline-sensitive membrane electrode

A choline-sensitive membrane electrode made with potassium tetrakis(p-chlorophenyl) borate as the exchanger and o-nitrophenyl phenyl ether as membrane solvent in poly (vinyl chloride) was almost insensitive to the surfactant sodium deoxycholate. By using this electrode, choline ( 10^?5 M) formed by the enzymatic hydrolysis of phosphatidylcholine with phospholipase D in the presence of sodium deoxycholate as activator was successfully measured. The method was applied to the determination of phosphatidylcholine in serum.     

Enzymatic Ring‐Opening Polymerization of Oxiranes and Dicarboxylic Anhydrides

Oxiranes, such as glycidyl phenyl ether, benzyl glycidate, glycidyl methyl ether, and styrene oxide, were copolymerized with dicarboxylic anhydrides, such as succinic anhydride, phthalic anhydride, and maleic anhydride, by the action of an enzyme in a stepwise reaction to produce the corresponding polyesters containing some ether linkages having a maximum M _w of 13 500. Oxiranes, such as glycidol and glycidyl phenyl ether, were also homopolymerized and copolymerized with other oxiranes by the enzyme to produce the corresponding polyethers.

Enzymatic polymerization of oxiranes and dicarboxylic anhydrides.     

Application of novel polymers with S‐alkylsulfonium salt moieties as alkylating agents and thermal latent cationic initiators

Sulfonium‐containing polymers prepared from dibenzothiophene and diphenyl sulfide were applied as both alkylating agents and latent initiators for the cationic polymerization of glycidyl phenyl ether. The alkylation of acetonitrile proceeded smoothly with poly(S‐n‐octyl‐2‐vinyldibenzothiophenium tetrafluoroborate) ( 4 ; 64 mol % octyldibenzothiophenium tetrafluoroborate unit) to give N‐(n‐octyl)acetamide in an excellent yield on the basis of the starting octyldibenzothiophenium tetrafluoroborate unit in 4 . The cationic polymerization of glycidyl phenyl ether was also carried out in the presence of poly(S‐methyl‐2‐vinyldibenzothiophenium tetrafluoroborate) or poly(S‐n‐octyl‐4‐vinyldiphenylsulfonium tetrafluoroborate) to confirm their moderate thermal latent activity. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3928–3933, 2001     

Syntheses and properties of new aromatic polybenzoxazoles bearing ether and phenylethylidene or 1‐phenyl‐2,2,2‐trifluoroethylidene linkages

Two new bis(ether acyl chloride)s, 1,1‐bis[4‐(4‐chloroformylphenoxy)phenyl]‐1‐phenylethane and 1,1‐bis[4‐(4‐chloroformylphenoxy)phenyl]‐1‐phenyl‐2,2,2‐trifluoroethane, were prepared from readily available reagents. Aromatic polybenzoxazoles with both ether and phenylethylidene or 1‐phenyl‐2,2,2‐trifluoroethylidene linkages between phenylene units were obtained by a conventional two‐step procedure including the low‐temperature solution polycondensation of the bis(ether acyl chloride)s with three bis(o‐aminophenol)s, yielding poly(o‐hydroxyamide) precursors, and subsequent thermal cyclodehydration. The intermediate poly(o‐hydroxyamide)s exhibited inherent viscosities of 0.39–0.98 dL/g. All of the poly(o‐hydroxyamide)s were amorphous and soluble in polar organic solvents such as N,N‐dimethylacetamide, and most of them could afford flexible and tough films via solvent casting. The poly(o‐hydroxyamide)s exhibited glass‐transition temperatures (T_g's) of 129–194 °C and could be thermally converted into corresponding polybenzoxazoles in the solid state at temperatures higher than 300 °C. All the polybenzoxazoles were amorphous and showed an enhanced T_g but a dramatically decreased solubility with to respect to their poly(o‐hydroxyamide) precursors. They exhibited T_g's of 216–236 °C through differential scanning calorimetry and were stable up to 500 °C in nitrogen or air, with 10% weight‐loss temperatures being recorded between 538 and 562 °C in nitrogen or air. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 914–921, 2003     

Synthesis and properties of novel cardo aromatic poly(ether‐benzoxazole)s

Three new bis(ether‐acyl chloride) monomers, 1,1‐bis[4‐(4‐chloroformylphenoxy)phenyl]cyclohexane ( 1a ), 5,5‐bis[4‐(4‐chloroformylphenoxy)phenyl]‐4,7‐methanohexahydroindan ( 1b ), and 9,9‐bis[4‐(4‐chloroformylphenoxy)phenyl]fluorene ( 1c ), were synthesized from readily available compounds. Aromatic polybenzoxazoles bearing ether and cardo groups were obtained by the low‐temperature solution polycondensation of the bis(ether‐acyl chloride)s with three bis(aminophenol)s and the subsequent thermal cyclodehydration of the resultant poly(o‐hydroxy amide)s. The intermediate poly(o‐hydroxy amide)s exhibited inherent viscosities in the range of 0.35–0.71 dL/g. All of the poly(o‐hydroxy amide)s were amorphous and soluble in many organic polar solvents, and most of them could afford flexible and tough films by solvent casting. The poly(o‐hydroxy amide)s exhibited glass‐transition temperatures (T_g's) in the range of 141–169 °C and could be thermally converted into the corresponding polybenzoxazoles approximately in the region of 240–350 °C, as indicated by the DSC thermograms. Flexible and tough films of polybenzoxazoles could be obtained by thermal cyclodehydration of the poly(o‐hydroxy amide) films. All the polybenzoxazoles were amorphous and showed an enhanced T_g but a dramatically decreased solubility as compared with their poly(o‐hydroxy amide) precursors. They exhibited T_g's of 215–272 °C by DSC and showed insignificant weight loss before 500 °C in nitrogen or air. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 4014–4021, 2001     

N-p-toluenesulfonyl-2-oxazolidones Via the cycloaddition reaction of p-tolucnesulfonyl isocyanate and epoxides

The reaction of styrene oxide and phenyl glycidyl ether with p-toluenesulfonyl isocyanate, employing a hydrocarbon-soluble adduct of tributylphosphine oxide and lithium bromide as catalyst, results in excellent yields of the N-p-toluenesulfonyl-2-oxazoIidones. The 5-isomeric-2-oxazolidone is obtained from phenyl glycidyl ether, but in contrast to conventional isocyanates, the p-toluenesulfonyl isocyanate, upon reaction with styrene oxide, produces the 4-isomeric 2-oxazolidone as the major product. The effect of the N-sulfonyl group on the nmr spectra of 2-oxazolidones is discussed.     

Synthesis and activity of aryl benzyl methyl sulfonium salts as cationic initiators: Effect of substituent on aryl group

Benzyl o-, m-, and p-substituted phenyl methyl sulfonium salts ( 2b – 2g ) were synthesized and their activities as cationic initiators were evaluated in the bulk polymerization of phenyl glycidyl ether (PGE). Especially, their activities were estimated with respect to the effect of substituents on the aryl groups. In the polymerizations of PGE with a series of benzyl p-substituted phenyl methyl sulfonium salts, the order of their activities was found to be 2c (CH₃OCOO) > 2b (CH₃COO) > 2d (CH₃O) ～ 2a (HO). In particular, 2c was the most active initiator of all, capable of initiating the polymerization of PGE even at room temperature. In the polymerizations with 2a, 2e (m-Cl), 2f (o-CH₃), and 2g (m-CH₃), the activity of 2e was the highest of all while those of 2a, 2f , and 2g were almost the same. These results strongly suggested that the electron-withdrawing group placed on the aryl group undoubtedly enhanced the activity of the sulfonium salts as the cationic initiators.     

Umlagerung von Allyl-aryläthern und Allyl-cyclohexadienonen mittels Bortrichlorid

Allyl aryl ethers which have no strongly electron attracting substituents undergo a charge-induced [3 s, 3 s] sigmatropic rearrangement in the prescence of 0.7 mole boron trichloride in chlorobenzene at low temperature, to give after hydrolysis the corresponding o-allyl phenols (Tables 1 and 2). The charge induction causes an increase in the reaction rate relative to the thermal Claisen rearrangement of ～10¹⁰. With the exception of allyl 3-methoxyphenyl ether (5) , m-substituted allyl aryl ethers show similar behaviour (with respect to the composition of the product mixture) to that observed in the thermal rearrangement (Table 3). The rearrangement of allyl aryl ethers with an alkyl group in the o-position, in the prescence of boron trichloride, yields a mixture of o- and p-allyl phenols, where more p-product is present than in the corresponding product mixture from the thermal rearrangement (Table 4). This ‘para-effect’ is especially noticeable for o-alkylated α-methylallyl aryl ethers (Table 5 ). With boron trichloride, 2,6-dialkylated allyl aryl ethers give reaction products which arise, in each case, from a sequence of an ortho-Claisen rearrangement followed by a [1,2]-, [3,3]- or [3,4]-shift of the allyl moiety (Tables 6 and 7). Ally1 mesityl ether (80), with boron trichloride, gives pure 3-ally1 mesitol ( 95 ). From phenol, penta-ally1 phenol ( 101 ) can be obtained by a total of five O-allylations followed by three thermal and two boron trichloride-induced rearrangements. The sigmatropic rearrangements of the ethers studied, using D- and ¹⁴C-labelled compounds, are collected in scheme 2; only the reaction steps indicated by heavy arrows are of importance. With protic acids, there is a [3,3]-shift of the allyl group in 6-allyl-2,6-disubstituted cyclohexa-2,4-dien-l-ones, while with boron trichloride the [3,3]-reaction is also observed along with the much less important [1,2]- and [3,4]-transformations (Table 8). 4-Allyl-4-alkyl-cyclohexa-2,5-dien-1-ones give only [3,3]-rearrangements with boron trichloride (Table 9). As expected, the naphthalenone 112 , which is formed by allowing boron trichloridc to react for a short time with allyl (1-methyl-2-naphthyl) ether ( 111 ), undergoes only a [3,4] rearrangement (Scheme 3). Representations of how, in our opinion, the complex behaviour of allyl aryl ethers and allyl cyclohexadienones under the influence of boron trichloride, can be rationalized are collected together in Schemes 4 and 5. In the last part of the discussion section, the steric factors leading to the appearance of the ‘para-effect’, are dealt with (Scheme 6).     

系列单取代烷氧基-2-羟丙基-β-环糊精的合成与表征

以环氧氯丙烷和脂肪醇为原料, 通过相转移催化法合成了乙基、正丙基、正丁基和正戊基缩水甘油醚(1～4), 并利用所合成的缩水甘油醚和β-环糊精为原料, 分别在弱碱水溶液(1.5%)和强碱水溶液(30%)中制备并用硅胶柱分离出单2位取代的乙氧基、丙氧基、丁氧基和戊氧基-2-羟丙基-β-环糊精(1a～4a)和单6位取代的丙氧基、丁氧基和戊氧基-2-羟丙基-β-环糊精(2b～4b), 利用薄层色谱、红外光谱、差热扫描量热分析、质谱和核磁共振等手段对所合成的产品进行了表征.     

Cationic polymerization of vinyl monomers initiated by 10-methylphenothiazine cation radicals

A small quantity of 10-methylphenothiazine cation radical (MPT^.+), electrochemically prepared and stocked in acetonitrile solution, initiated cationic polymerizations of n-butyl, t-butyl, and 2-methoxyethyl vinyl ethers and p-methoxystyrene, while no initiation occurred for phenyl vinyl ether, styrene, methyl methacrylate, and phenyl glycidyl ether. ¹H-NMR studies of oligomers and low molecular weight compounds isolated from the reaction mixture for the polymerization of t-butyl vinyl ether in the presence of a small amount of D₂O indicated that electron transfer from the monomer to MPT^.+ was involved in the initiation step. ¹H- and ¹³C-NMR and MO calculation implied that monomers with higher electron densities on the vinyl groups and with lower ionization potentials were more susceptible to the initiation of MPT^.+. © 1994 John Wiley & Sons, Inc.     

Alternating copolymerization of 2,3-dichloro-5,6-dicyano-p-benzoquinone with styrene and polymerization behavior with vinyloxy compounds

2,3-Dichloro-5,6-dicyano-p-benzoquinone (DDQ) was found to copolymerize alternatingly with styrene (St). DDQ–isobutyl vinyl ether and DDQ–2-chloroethyl vinyl ether systems gave homopolymers of vinyl ethers, while DDQ–phenyl vinyl ether and DDQ–vinyl acetate systems gave oligomers containing both monomer units. In the terpolymerization of DDQ, p-chloranil (pCA), and St, terpolymers obtained were found to have about 50 mole % of St units regardless of monomer feed ratio and DDQ was incorporated much more rapidly into the terpolymer than pCA. The difference in the reactivity of the acceptor monomers could be attributed to that in their electron-accepting character.     

Polymerization of glycidol and its derivatives: A new rearrangement polymerization

Anionic (KOH) polymerization of glycidol, or its trimethylsilyl ether (TMSGE) followed by hydrolysis, gives a low molecular weight, largely amorphous polymer that is not the reported 1,3-polyglycidol but, based on ¹³C-NMR, largely a 1,4-poly(3-hydroxyoxetane) with much branching. This result is achieved by a simple rearrangement of the usual, propagating secondary oxyanion to a primary one. Substantial amounts of four dimers (5–10%), four trimers, and some tetramers were also found. One dimer was isolated and shown to be glycidyl glycerin, the usual thermal dimer from glycidol. Possible structures of the other dimers are proposed. The polymerization appears to begin with the rapid formation of the glycidoxy anion , formed by base abstraction of a proton from glycidol and by nucleophilic displacement of the SiMe₃ group from TMSGE. Other bases such as KOtert-Bu give similar 1,4 polymer for glycidol but, with TMSGE, there is considerable 1,3 polymerization. Detailed mechanisms are proposed. The polymer perpared from R-TMSGE with KOH was highly crystalline, high melting (166°C), H₂O soluble, isotactic poly(3-hydroxyoxetane). The cationic polymerization of tert-butyl glycidyl ether (TBGE) and TMSGE gave low molecular weight 1,3 polyethers. The TBGE polymer was all head-to-tail whereas the polyglycidol from TMSGE contained extensive head-to-head chain units with considerable branching. Mechanisms for these interesting differences are proposed.     

Anionic alternating copolymerization of 3,4‐dihydrocoumarin and glycidyl ethers: A new approach to polyester synthesis

Anionic copolymerizations of 3,4‐dihydrocoumarin (DHCM) and a series of glycidyl ethers (n‐butyl glycidyl ether, tert‐butyl glycidyl ether, and allyl glycidyl ether) with 2‐ethyl‐4‐methylimidazole as an initiator proceeded in a 1:1 alternating manner to give the corresponding polyesters, whose structures were confirmed by spectroscopic analyses and reductive scission of the ester bonds in the main chain with lithium aluminum hydride, followed by detailed analyses of the resulting fragments. The polyester obtained by the copolymerization of DHCM and allyl glycidyl ether inherited the allyl groups in the side chain, whose applicability to chemical modifications of the polyester was successfully demonstrated by a platinum‐catalyzed hydrosilylation reaction. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 4092–4102, 2008     

Synthesis and characterization of certain new poly(bisimide)s. I

Maleic and citraconic anhydrides were reacted with several diamines to obtain a novel class of high temperature resistant bisimides.^1–3 The bisimides were characterized by melting points, elemental analysis, UV–Vis, ¹H- and ¹³C-NMR, and mass spectral analysis. The bisimide monomers were then polymerized by the addition process. A poly(amidemaleimide) was also synthesized by reacting maleic anhydride with p-aminobenzhydrazide. The thermal stability of these highly crosslinked poly(bisimide)s were examined by TGA and DTA. A neat bisimide monomer obtained from 2,2′-bis[4(p-aminophenoxy)phenyl] propane with maleic anhydride namely, 2,2′-bis[4-(p-maleimidophenoxy)phenyl]propane was reacted with 2,2′-bis[4(p-aminophenoxy)phenyl]propane by the Michael reaction.⁴ A fiber glass cloth reinforced laminate was prepared from bismaleimide and amine mixture and the mechanical properties of the test laminate evaluated.