bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Dependence of the Polarity of Solvents on 1,3 : 2,4-Di-O-benzylidene-d-sorbitol Gel
Authors: Yamasaki Seiji , Tsutsumi Hisao 
Published: July 2006

Abstract
1,3 : 2,4-Di-O-benzylidene-d-sorbitol (d-DBS) is known as a chiral oil gelator for a wide variety of organic solvents. The relationship between texture, structure of the gel, and the aggregated structure formed by d-DBS was investigated in various solvents. In the low polar solvents, the gel held a mesh type network structure in which the fiber appeared to be a rope-like helical structure. In the moderately polar solvents, the gel held an isotropic mesophase, but in the polar solvents, a spherulite texture was observed. From the experiments for the critical gel concentration of d-DBS in various solvents, it is assumed that there are three regions that differ in the form of hydrogen bonding, depending upon the polarity of solvents. By IR spectroscopic measurements, we found that, with the increase of solvent polarity, the hydrogen bonding between d-DBS and the solvent became more predominant than the intramolecular hydrogen bonding, and the hydrogen bonding between d-DBS became weaker at the same time. In addition, the intensities of CD spectra in the d-DBS gel decreased according to the increase of the solvent polarity. Here it is considered that textures and structurs observed in the gel are related to the aggregated structure that is mainly formed through hydrogen bonding among d-DBS.
An Equation of State for the Self-Diffusion Coefficient in Lennard–Jones Fluid Derived by Molecular Dynamics Simulations
Authors: Kataoka Yosuke , Fujita Minoru 
Published: July 2006

Abstract
The self-diffusion coefficient in Lennard–Jones fluid was studied by molecular dynamics simulation. Simulations were done at 414 states in the temperature–volume plane. An equation of state for the self-diffusion coefficient was derived by the least-square fitting. The calculated equation of state was in agreement with the experimental results on CO2. Its pressure dependence was also consistent with that in liquid hexane. The liquid structure was analyzed by the excess coordination number, the distributions of the cluster size and the hole volume. The volume dependence of the self-diffusion coefficient in the two-phase region was discussed in terms of the coordination number in the first shell.
Raman Polarizability for Some Totally Symmetric Normal Vibrations of Naphthalene and Maleic Anhydride
Authors: Shimizu Fumio , Nibu Yoshinori , Osaki Tomoe , Shimada Hiroko , Shimada Ryoichi 
Published: July 2006

Abstract
The values of the Raman polarizability of some totally symmetric normal vibrations of naphthalene and maleic anhydride were estimated from the analysis of the polarized Raman spectra observed in single crystal. For the totally symmetric ring vibrations of naphthalene the principal elements of the Raman polarizability in the molecular plane are about isotropic and the principal element perpendicular to the molecular plane has the value almost one-half of the values of the in-plane elements. For the totally symmetric C=O and C=C stretching vibrations of maleic anhydride the Raman polarizability shows quite anisotropic character.
Recent Advances in Aerobic Oxygenation
Authors: Mukaiyama Teruaki , Yamada Tohru 
Published: July 2006

Abstract
Recent advances in the aerobic oxygenations of olefins using transition-metal complex catalysts are reviewed. The main topics focused on are the cobalt(II)-complex-catalyzed oxygenation of olefins, nickel(II)-complex-catalyzed aerobic epoxidation, enantioselective, aerobic epoxidation using chiral manganese(III) complex catalysts, aerobic Baeyer–Villiger oxidation and direct oxygenation of aromatic compounds.
Steric Control of Selectivity for Lanthanoids in Liquid–Liquid Extraction with Tris- and Tetrakis(pyrazol-1-yl)borate–β-Diketon Mixed-Ligand Systems
Authors: Kokusen Hisao , Sohrin Yoshiki , Hasegawa Hiroshi , Kihara Sorin , Matsui Masakazu 
Published: July 2006

Abstract
Mixed-ligand chelate extraction of trivalent lanthanoid ions (M3+) into benzene with poly(pyrazol-1-yl)borate (HnB(pz)4−n; n = 0, 1) and β-diketone was studied. The β-diketones used were dibenzoylmethane (dbm) and dipivaloylmethane (dpm). Lanthanoid ions were extracted as [M{HnB(pz)4−n}2(β-diketone)]. The logarithmic extraction constants (log Kex) of the [HB(pz)3]− systems were 5—6 higher than those of the [B(pz)4]− systems. The highest separability for lanthanide ions was achieved with the [B(pz)4]−– dbm system. These features of log Kex were principally governed by intra- and interligand steric contact.
Photochemistry of μ-Amido-μ-hyperoxo-dicobalt(III) Complexes with Ammine and Polyamine Ligands in Aqueous Solutions: Effects of Ligand and pH
Authors: Shinohara Nobuyoshi , Shibukawa Hirohiko , Shinozaki Kazuteru , Yoshikai Mika 
Published: July 2006

Abstract
Photolyses of μ-amido-μ-hyperoxo-dicobalt(III) complexes, [LCo(NH2,O2−)CoL]4+ (L = 4NH3 (1), en + 2NH3 (2), 2en (3), tren (4)), (tren: 2,2′,2″-triaminotriethylamine, en: ethylenediamine) were investigated. The photolysis of complex 4 in a neutral aqueous solution produced a μ-hydroxo-μ-peroxo-dicobalt(III) complex, [(tren)Co(OH,O22−)Co(tren)]3+, together with a mononuclear cobalt(III) complex, [Co(NH3)(tren)(H2O)]3+. A mononuclear complex and Co2+ were produced in the photolyses of μ-hyperoxo complexes 1 and 2 containing NH3 ligand in neutral aqueous solutions. In acidic media, only mononuclear complex and Co2+ were produced in the photolysis of all μ-hyperoxo complexes examined. Quantum yields of the complexes with NH3 increased with increasing the number of coordinated NH3 (φ = 0.25, 0.11, 0.023, and 0.028 for complexes 1, 2, 3, and 4, respectively, at 365 nm irradiation in neutral region). The quantum yields obtained in acidic solutions were similar in magnitude to those obtained in neutral solutions.
Model Reaction of Self-Condensation of Sulfenic Acids. Kinetic Investigation for the Reaction of Methyl Benzenesulfenate with trans-Decalin-9-sulfenic Acid and 2-Methyl-2-propanesulfenic Acid
Authors: Yoshimura Toshiaki , Hamada Kazuhiro , Yamazaki Satoru , Shimasaki Choichiro , Ono Shin , Tsukurimichi Eiichi 
Published: July 2006

Abstract
Reaction of 2-methyl-2-propanesulfenic acid (1) with methyl arenesulfenates (2) gave S-aryl 2-methyl-2-propanethiosulfinates quantitatively, and kinetic investigation was carried out. Second-order rate dependence (first-order in methyl benzenesulfenate (2a) and first-order in the sulfenic acid (1)) was observed, and a small activation enthalpy (ΔH‡ = 28 kJ mol−1) and a large negative activation entropy (ΔS‡ = −130 J K−1 mol−1) were obtained. Kinetics for the reaction of trans-decalin-9-sulfenic acid (3) with the sulfenates 2 under acidic conditions in methanol–water gave the observation of the second-order dependence, a small activation enthalpy (ΔH‡ = 30.5 kJ mol−1), a large negative activation entropy (ΔS‡ = −140 J K−1 mol−1), a large negative Hammett ρ-value (ρ = −1.39) and no solvent isotope effect (kMeOH/kMeOD = 1.10—1.14 in the range of 15.64—29.98 °C). Kinetics for acidic hydrolysis of the sulfenate 2 under the same conditions afforded the similar activation parameters (ΔH‡ = 40.7 kJ mol−1, ΔS‡ = −200 J K−1 mol−1 at [H2O] = 0.80 × 10−3mol dm−3) and a larger negative Hammett ρ-value (ρ = −2.22) than that for the reaction of the sulfenic acid 3 with the sulfenate 2. From these results, structures of the transition state for both the self-condensation of sulfenic acid and the hydrolysis of the sulfenate ester 2 were discussed. The reaction of sulfenate esters 2 with stable sulfenic acids is a good model for studying the self-condensation of sulfenic acids.
Physalins Possessing an Endoperoxy Structure from Physalis alkekengi var. francheti. Structural Revision of Physalin K
Authors: Makino Bunsho , Kawai Masao , Iwata Yasushi , Yamamura Hatsuo , Butsugan Yasuo , Ogawa Kiyoshi , Hayashi Mitsuo 
Published: July 2006

Abstract
Physalin K was isolated from Physalis alkekengi var. francheti. Spectroscopic studies and chemical correlations, however, revealed that the reported structure of physalin K at the AB ring moiety, namely, 4α,5α-epoxy-6α-hydroxy-2-en-1-one, should be revised to 2α,5α-epidioxy-6β-hydroxy-3-en-1-one. A new physalin, named physalin Q, was also isolated and identified as the 2β,5β-epidioxy diastereomer of physalin K.
Facile Synthesis of Thiolariat Ethers or Crown Ethers Containing a Mercapto Group as a Side Arm
Authors: Nabeshima Tatsuya , Tsukada Naoko , Haruyama Tsutomu , Yano Yumihiko 
Published: July 2006

Abstract
Cyclization reaction of S-substituted thioglycerol and oligoethylene glycol ditosylate gave thiolariat ethers in moderate yields. Mercaptomethyl crown ethers were obtained easily from benzylthiomethyl crown ethers by Na in liq. NH3–BuOH.
Observation of the Adsorption of Cytochrome c and Glucose Oxidase onto an Amphiphilic Monolayer at an Air/Water Interface by the Reflection Spectroscopy of Visible Radiation
Authors: Ohnishi Michihiro , Ishimoto Coe , Seto Jun’etsu 
Published: July 2006

Abstract
The adsorption of two kinds of chromoproteins, cytochrome c and glucose oxidase, was observed at an air/water interface by reflection spectroscopy using optical fibers. The relation between the adsorption of cytochrome c onto an amphiphilic monolayer and the deposition of the monolayer with cytochrome c by the Langmuir–Blodgett (LB) technique was clarified. It was found out that a good Y-type LB film, with a transfer ratio of 0.9—1.0, was obtained when the adsorbed area of cytochrome c was less than about 84% of the maximum average coverage. The reflection spectrum of glucose oxidase, not as such, but stained with coomassie brilliant blue (CBB), could be successfully observed. Since CBB is applicable to almost any protein, the reflection spectroscopy of almost any protein, not only chromoproteins, is possible.
Triarylcarbenium Salts Highly Reducible by Primary Alcohols
Authors: Wada Masanori , Mishima Hisashi , Watanabe Tetsuya , Natsume Satoko , Konishi Hideki , Kirishima Katsuhiko , Hayase Shuichi , Erabi Tatsuo 
Published: July 2006

Abstract
A series of triarylmethanols bearing o-methoxyl groups (1a: [2,6-(MeO)2C6H3]3COH, 1b: (2-MeOC6H4)[2,6-(MeO)2C6H3]2COH, 1c: Ph[2,6-(MeO)2C6H3]2COH, 1d: [2,5-(MeO)2C6H3]3COH, 1e: Ph2[2,6-(MeO)2C6H3]COH) were prepared. Corresponding carbenium salts, [Ar3C]X 2a—c, were isolated by short-period treatments of Ar3COH 1a—c with a slight excess of acid in some bulky alcohols, such as 2-propanol or 2-methyl-1-propanol. The high basicity of 1a—c was explained by through-space interactions of a pair of 2p electrons of an o-methoxyl oxygen with an empty 2p orbital of the resulting carbenium carbon. In ethanol, 1-butanol or 3-methyl-1-butanol, 1c, as well as 2c, was reduced under very mild conditions to triarylmethane, Ar3C–H 3c, and in other bulkier alcohols it was reduced under more forcing conditions. The formations of aldehyde or ketone, the by-product, were confirmed in some cases. Compounds 1a,b,d,e, as well as 2a,b, reacted in analogous manners under more forcing conditions. The reaction rates in several alcohols increased in the order 2a &lt; 2b &lt; 2c, and the reaction rates of alcohol for 2c decreased in the order ethanol &gt; 3-methyl-1-butanol &gt; 1-butanol &gt; 2-propanol &gt; methanol &gt; 2-butanol &gt; 2-methyl-1-propanol. Compounds 2b,c were also reduced in tetrahydrofuran, and formed xanthene derivatives in dimethyl sulfoxide or in water.
Nucleophile-Induced Ring Enlargement of 1-(1-Iodoalkyl)silacyclobutane and 1-(1,2-Epoxyalkyl)silacyclobutane into Silacyclopentane. Application to the Syntheses of 1,4-Diol, 4-Alken-1-ol, and 1,4,5-Triol
Authors: Matsumoto Kozo , Takeyama Yoshihiro , Miura Katsukiyo , Oshima Koichiro , Utimoto Kiitiro 
Published: July 2006

Abstract
Two methods for ring enlargement of silacyclobutane into silacyclopentane have been described. (1) Treatment of 1-(1-iodoalkyl)silacyclobutane with t-BuOK or AgOAc provided 2-alkyl-1-silacyclopentanes which were easily converted into 1,4-diols by oxidative cleavage of carbon–silicon bond. (2) An addition of i-PrOLi to 1-[(Z)-1,2-epoxyhexyl]-1-methylsilacyclobutane gave erythro-2-(1-hydroxypentyl)-1-isopropoxy-1-methylsilacyclopentane, which was converted into (Z)-4-nonen-1-ol, (E)-4-nonen-1-ol, or 1,4,5-nonanetriol.
Sequential Electron Transfer Leading to Long-Lived Charge Separated State in a Porphyrin–Oxochlorin–Pyromellitdimide Triad
Authors: Osuka Atsuhiro , Marumo Shinji , Maruyama Kazuhiro , Mataga Noboru , Tanaka Yoshinori , Taniguchi Seiji , Okada Tadashi , Yamazaki Iwao , Nishimura Yoshinobu 
Published: July 2006

Abstract
The synthesis and excited-state dynamics are described for fixed-distance porphyrin–oxochlorin–pyromellitdimide triads (P–C–Im) and related reference compounds. In zinc-oxochlorin–pyromellitdimide (ZnP–Im), the 1(ZnC)* is quenched by the attached Im through intramolecular charge separation (CS) in benzene, THF, and DMF, while the 1(H2C)* in the corresponding free base is not significantly quenched by the Im even in polar DMF. In the steady-state fluorescence emission spectra, only the emission from the 1(C)* is commonly observed, indicating an efficient intramolecular singlet–singlet excitation energy transfer from P to C. Of these, the fluorescence intensities of the 1(H2C)* in ZnP–H2C and ZnP–H2C–Im are significantly reduced in polar DMF solution and this is attributed to the intramolecular CS that gives (ZnP)+–(H2C)−–Im and (ZnP)+–(H2C)−, respectively. The (ZnP)+–(H2C)−–Im ion pair is clearly shown, by picosecond absorption spectroscopy, to be converted into a secondary, longer-lived charge separated state (ZnP)+–H2C–(Im)− via charge-shift reaction in competition with wasteful charge recombination to the ground state. The (ZnP)+–H2C–(Im)− state is formed in 0.09 quantum yield from ZnP–1(H2C)*–Im and has a lifetime of 0.24 μs in DMF.
Ring Enlargement of α-Ethylidenecycloalkanones to β-Alkylidenecycloalkanones Induced by Trimethylstannyllithium/Aldehyde Equivalents/Lewis Acids
Authors: Fujiwara Jun , Tokuyasu Jin , Sato Tadashi 
Published: July 2006

Abstract
α-Ethylidenecycloalkanones underwent a ring enlargement to β-alkylidenecycloalkanones upon a treatment with trimethylstannyllithium/aldehyde equivalents/Lewis acids with high stereoselectivity.
A New Approach to dl-Cannabichromene
Authors: Yamaguchi Seiji , Shouji Noriaki , Kuroda Kazuyoshi 
Published: July 2006

Abstract
Natural dl-cannabichromene was synthesized in 6 steps from methyl 5-methoxy-2-methyl-7-pentyl-2H-chromen-2-acetate prepared by the cyclization of 2-hydroxy-6-methoxy-4-pentylbenzaldehyde with dimethyl isopropylidenemalonate.
Oxidative Generation of α-Radicals of Carbonyl Compounds from the α-Stannyl Derivatives and Their Reactions with Electron-Rich Olefins
Authors: Kohno Yasushi , Narasaka Koichi 
Published: July 2006

Abstract
The oxidation of α-tributylstannyl alkanoates with tetrabutylammonium hexanitratocerate(IV) generates α-radicals of the alkanoates by eliminating the stannylium ion. The thus-formed radicals react with various electron-rich olefinic compounds, such as silyl enol ethers, giving addition products in good yield. This method formally achieves selective cross coupling between alkanoates and ketones.
Preparation of S-Protected Cysteine-Containing Peptide Thioester and Its Use for the Synthesis of the Barnase-Like Domain in DNA-Directed RNA Polymerase II of Saccharomyces cerevisiae
Authors: Hojo Hironobu , Yoshimura Shoko , Go Mitiko , Aimoto Saburo 
Published: July 2006

Abstract
The Barnase-like Domain in DNA-Directed RNA Polymerase II of Saccharomyces cerevisiae containing three cysteine residues was synthesized by a thioester method. A partially-protected cysteine-containing peptide thioester was prepared via a peptide obtained by a solid-phase method using 3-nitro-2-pyridinesulfenyl amino acid derivatives. Four peptide segments covering 112 amino acid residues of the barnase-like domain were condensed from the C-terminal to the N-terminal one by one in the presence of silver ions and N-hydroxysuccinimide to give a full sequence peptide. RNase activity of the synthetic domain could not be detected because of its extreme low solubility in the neutral buffer.
Thermal Rearrangement of N-Alkyl-, and N-Aryl-(2,2-dihalo-1-phenylcyclopropyl)methyleneamines to 1-Alkyl-, and 1-Aryl-2 (or 3)-halo-4-phenylpyrroles
Authors: Kagabu Shinzo , Tsuji Hideaki , Kawai Itsumi , Ozeki Hitomi 
Published: July 2006

Abstract
The thermolysis of N-t-alkyl-, and N-aryl-(2,2-dichlorocyclopropyl)methyleneamines yielded directly 1-t-alkyl, and 1-aryl-3-chloropyrroles as the major products along with a slight amount of the 2-chloro isomers. The transformation to the 3-chloropyrroles was enhanced in polar solvents. But basic additives directed the thermal rearrangement into the 1,2-bond cleavage of the cyclopropane ring, leading to the 2-chloropyrroles. On the other hand, (difluorocyclopropyl)methyleneamines were pyrolyzed exclusively to 3-fluoropyrroles under 1,3-bond cleavage. The ionic mechanism involving a heterolytic dissociation of chlorine atom under 1,3-bond scission of the cyclopropane ring is proposed for the rearrangement to 3-chloropyrroles, while a homolytic cleavage pathway is proposed for 3-fluoropyrroles. The present thermolysis supplies a unique preparative tool for 2-, and 3-halo-4-phenylpyrrole derivatives.
Stereoselective Organic Synthesis via Dynamic Kinetic Resolution
Authors: Noyori Ryoji , Tokunaga Makoto , Kitamura Masato 
Published: July 2006

Abstract
Asymmetric catalysts, either chemical or biological, effect the reactions of enantiomeric substrates at unequal rates, allowing for the kinetic resolution of racemates. The asymmetric reaction of chirally labile compounds capable of undergoing in situ racemization can, in principle, afford a single stereoisomer in 100% ee and in 100% yield. The second-order reaction provides a powerful tool for the stereoselective synthesis of chiral compounds, as exemplified by, among others, the biochemical hydrolysis of hydantoins or oxazolinones and microbial reductions or BINAP–Ru(II) catalyzed hydrogenation of certain α-substituted β-keto esters. Such transformations are characterized by the presence of parallel reactions interrelated by the stereoinversion of the enantiomeric substrates. The efficiency is decisively affected by the kinetic parameters, particularly the relative rates of the stereoinversion and reaction as well as the intrinsic stereochemical parameters of the catalyst and substrate. Such stereoselective reactions via dynamic kinetic resolution are expressed mathematically and the stereochemical profiles are displayed graphically. The validity of this basic approach has been verified by the correlation to the experimental results.
Synthesis of Artificial HMG-CoA Reductase Inhibitors Based on the Olefination Strategy
Authors: Hiyama Tamejiro , Minami Tatsuya , Takahashi Kyoko 
Published: July 2006

Abstract
Synthetic methods were studied for optically active 6-oxo-3,5-isopropylidenedioxyhexanoate esters (4), which could be used as a key precursor of various kinds of artificial analogs of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors. An enantiomer (+)-4 was prepared by asymmetric reduction of β,δ-diketo esters derived from the Taber’s alcohol or l-tartrate followed by a series of chemical transformations, and the desired enantiomer (−)-4 was prepared by the same asymmetric reduction starting from d-tartrate. The key intermediate (−)-4 was finally converted into a highly potent HMG-CoA reductase inhibitor, NK-104.
Beckmann Rearrangement of Oximes Catalyzed with Tetrabutylammonium Perrhenate and Trifluoromethanesulfonic Acid
Authors: Kusama Hiroyuki , Yamashita Yuko , Narasaka Koichi 
Published: July 2006

Abstract
The Beckmann rearrangement of oximes is catalyzed by a combined use of tetrabutylammonium perrhenate (Bu4NReO4) and trifluoromethanesulfonic acid in nitromethane under azeotropic conditions, giving amides in high yield. By employing this catalytic system, amides can be prepared directly from ketones and hydroxylamine hydrochloride.
Kinetic Study of the Electroreduction of Benzoic Acid
Authors: Cheng Po-Chung , Nonaka Tsutomu 
Published: July 2006

Abstract
This work demonstrates the procedures needed to extract kinetic parameters from experimental data and to establish a reasonable model for the electroreduction of benzoic acid in a citrate buffer solution, a reaction typical of consecutive electrochemical reactions with solvent decomposition. Influences of operating conditions (current density, flow rate, etc.) on the formation ratio of benzaldehyde to benzyl alcohol were examined in a flow cell system with a lead cathode. Three reaction mechanism models taking into account dehydration and mass transfer of a hydrated benzaldehyde intermediate were discussed. Numerical calculations showed that the electrolyte in the vicinity of the cathode during an electrolysis was weakly alkaline. Factors controlling the product-selectivity of benzaldehyde are also discussed on the basis of simulation.
Highly Effective Dehydrogenation of Cyclohexanol to Cyclohexanone over Carbon-Supported Cobalt Catalyst
Authors: Uemichi Yoshio , Shouji Kiyoshi , Sugioka Masatoshi , Kanazuka Takaji 
Published: July 2006

Abstract
The dehydrogenation of cyclohexanol to cyclohexanone has been studied over activated carbon-supported transition metals as catalysts. The Co/carbon catalyst was found to be highly effective for the reaction. Its catalytic behaviors strongly depended on the temperature of hydrogen reduction. Highly dispersed and well-reduced cobalt catalyst showed pronounced activity and stability.
Factors Affecting the Redispersibility of Organosilica Sols Prepared by a Modification of Silica Particles with a Polyol-Based Polymer
Authors: Kito Taketoshi , Yamaye Makoto , Yoshinaga Kohji , Ishihara Youichi , Komatsu Michio , Nishida Hiroyasu 
Published: July 2006

Abstract
Organosilica sols which were redispersible in nonpolar or less polar organic solvents were prepared by a chemical modification of the silica surface with a polyol-based coupling polymer; the redispersibility was then examined in terms of the molecular weight of the coupling polymer, charged coupling polymer/silica (mmol g−1) (P/S) ratio, and the size of modified silica particles. Fractionated coupling polymers with an Mw/Mn of 2.0—2.8 were used. The charged P/S ratio was a leading factor for the redispersibility. The redispersibility was achieved when the charged P/S ratio exceeded approximately 0.3 mmol g−1, using coupling polymers of various molecular weights. The particle size of the modified silica decreased along with an increase in the charged P/S ratio and the reaction time. The presence of a free polymer was not essential for the redispersibility when the saturation of the silica surface with the coupling polymer was nearly completed.
Polymerization of 1-(1-Naphthyl)-1-propyne by Nb and Ta Catalysts and Polymer Properties: Effects of the 1-Naphthyl Group
Authors: Kouzai Hiroaki , Masuda Toshio , Higashimura Toshinobu 
Published: July 2006

Abstract
1-(1-Naphthyl)-1-propyne polymerized in the presence of NbCl5–cocatalyst systems to give virtually selectively a new polymer ca. 3 × 105) in high yields. Catalysts based on TaCl5 produced mixtures of the polymer and cyclotrimers. The polymer was a pale-yellow solid soluble in various organic solvents (e.g., toluene, CHCl3), and formed a free-standing film on solution casting. The onset temperature of the weight loss of the polymer in air was ca. 340 °C, which is higher than that (280 °C) of poly(1-phenyl-1-propyne) [poly(1-PP)]. The oxygen permeability coefficient at 25 °C was 80 barrers and one order of magnitude higher than that of poly(1-PP). These results are explicable in terms of the steric effects of the 1-naphthyl group.