Photoinduced ionic polymerization. III. Cationic polymerization and copolymerization of cyclohexene oxide and α-methylstyrene in the presence of pyromellitic dianhydride

The photoinduced ionic polymerization of cyclohexene oxide was studied in the presence of pyromellitic dianhydride. The polymerization is initiated by the excited chargetransfer complex between cyclohexene oxide and the electron-acceptor and proceeds by a cationic mechanism. Photoinduced cationic polymerization of α-methylstyrene was also observed in the presence of pyromellitic dianhydride. The initiation mechanism of the polymerization was elucidated by means of electron spin resonance measurements. The concentration of pyromellitic dianhydride anion-radicals measured in this way was found to be proportional to the rate of polymerization. This result shows clearly that the photopolymerization is initiated by cation-radicals formed from photoexcited donoracceptor complexes. The attempted photocopolymerization of cyclohexene oxide and α-methylstyrene gave a mixture of homopolymers. The composition of the product depends on the wavelength of the light used.     

CO2 laser Stark spectroscopy of the Coriolis-coupled ν2 and ν5 bands of CD3Br

The ν₂ (CD₃ symmetrical deformation) and ν₅ (CD₃ degenerate deformation) fundamental bands of CD₃Br were studied by 9.4- and 10.4-μm CO₂ laser Stark spectroscopy. Stark resonances originating from 28 and 53 rovibrational transitions of the ν₂ and ν₅ bands, respectively, were assigned for each of the isotopic species, CD₃⁷⁹Br and CD₃⁸¹Br. These two bands were simultaneously analyzed with explicit inclusion of the ν₂-ν₅ Coriolis interaction, yielding precise molecular constants in the ν₂ and ν₅ excited states as well as the Coriolis coupling constant. The molecular constants obtained are consistent between the two isotopic species and are in good agreement with the results of high-resolution infrared studies. The band origins and dipole moments are

     

103.

A stannylene strategy for regioselective acylation and phosphorylation of 1,2-cyclohexylidene-myo-inositol. Its convenient resolution and phosphatidylinositol synthesis     

Yutaka Watanabe  Yoko Kiyosawa  Sayuri Hyodo  Minoru Hayashi 《Tetrahedron letters》2005,46(2):281-284

The bis(dibutylstannylene) derivative of 1,2-cyclohexylidene-myo-inositol reacted with (S)-O-acetylmandeloyl chloride and diphosphate tetraesters to give 3,6-dimandelate and 3-phosphate, respectively. Using the stannylene methodology for the optical resolution and regioselective phosphorylation of the ketal, a concise synthesis of phosphatidylinositol with the natural configuration was accomplished.     

104.

Preparation and characterization of high-specific-surface-area activated carbons from K2CO3-treated waste polyurethane   总被引：2，自引：0，他引：2  

Hayashi J  Yamamoto N  Horikawa T  Muroyama K  Gomes VG 《Journal of colloid and interface science》2005,290(2):437-443

An activated carbon with high specific surface area was prepared from polyurethane foam by chemical activation with K2CO3 and the influences of carbonization temperature and impregnation ratio on the pore structure of the prepared activated carbon were investigated. It was found that the specific surface area of the activated carbon was at a maximum value (about 2800 m(2)/g) at a carbonization temperature of 1073 K and at an impregnation ratio of 1.0. It was concluded that the polyurethane foam structure was modified during impregnation by K2CO3, K2CO3 promoted charring during carbonization, and then the weight loss behavior was changed below 700 and above 1000 K, carbon in the char was consumed by K2CO3 reduction, and this led to the high specific surface area. The prepared activated carbon had a very sharp micropore size distribution, compared with the commercial activated carbon having high specific surface area. The amounts of three organic vapors (benzene, acetone, and octane) adsorbed on the prepared activated carbons was much larger than those on the traditional coconut shell AC and the same as those on the commercial activated carbon except for octane. We surmised that the high specific surface area was due to the modification of the carbonization behavior of polyurethane foam by K2CO3.     

105.

Radiation-induced solid-state polymerization of trioxane under high pressure     

Yuzo Yamazawa  Tadashi Iwai  Akihiko Ito  Koichiro Hayashi 《Journal of polymer science. Part A, Polymer chemistry》1971,9(2):257-263

The in-source polymerization of trioxane in the solid state was investigated over a wide range of temperature and pressure, i.e., from 30 to 140°C and up to 7000 kg/cm², respectively. In the polymerization that was carried out slightly below the melting point under pressure, the higher the pressure, the higher the rate of polymerization. It was confirmed that the maximum rate of solid-state polymerization of trioxane occurs near the melting points, even under elevated pressure. The rate of polymerization decreased with increasing pressure at constant temperature. The shape of the time–conversion curves may be classified into two types, i.e., one which is typical of high pressure and low temperature, and the other which is typical of low pressure and high temperature. Changes in the shape of the conversion—intrinsic viscosity curves occurred coincidentally. Thus, three regions for the different “polymerization characteristic” were determined as functions of polymerization temperature and pressure. Explanations are given for the above-mentioned polymerization characteristic.     

106.

Catalytic direct 1,4-conjugate addition of aldehydes to vinylketones on secondary-amines immobilised in FSM-16 silica     

Shimizu K  Suzuki H  Hayashi E  Kodama T  Tsuchiya Y  Hagiwara H  Kitayama Y 《Chemical communications (Cambridge, England)》2002,(10):1068-1069

Direct 1,4-conjugate addition of naked aldehydes to vinylketones is catalysed effectively by N-methyl-3-aminopropylated FSM-16 mesoporous silica, which can be regarded as a novel heterogeneous catalysis for a practical C-C bond formation reaction.     

107.

Comparative characterization study of microporous carbons by HRTEM image analysis and gas adsorption   总被引：1，自引：0，他引：1  

Lozano-Castello D  Cazorla-Amoros D  Linares-Solano A  Oshida K  Miyazaki T  Kim YJ  Hayashi T  Endo M 《The journal of physical chemistry. B》2005,109(31):15032-15036

The present work presents a useful comparison of micropore size distributions (MPSDs) obtained from gas adsorption and image analysis of high-resolution transmission electron micrographs. It is shown that the MPSD obtained for a chemical activated carbon is concordant with that obtained from CO2 adsorption. In addition, this technique has allowed us to obtain the MPSD of a carbon molecular sieve (CMS) prepared in our laboratory by a copyrolysis process, which could only be characterized by CO2 adsorption at 273 K (not by N2 adsorption at 77 K due to diffusional problems). The MPSD obtained by high-resolution transmission electron microscopy (HRTEM) for the CMS is wider than that obtained by CO2 adsorption, suggesting that HRTEM is detecting the closed porosity existing in this sample, which is not accessible to gas adsorption. The existence of closed porosity in the CMS is explained considering the preparation method used. Thus, HRTEM combined with image analysis seems to be useful for structural analysis of narrow micropores including closed porosity.     

108.

Improvement in enzyme activity and stability by addition of low molecular weight polyethylene glycol to sodium bis(2-ethyl-L-hexyl)sulfosuccinate/isooctane reverse micellar system     

Talukder MM  Takeyama T  Hayashi Y  Wu JC  Kawanishi T  Shimizu N  Ogino C 《Applied biochemistry and biotechnology》2003,110(2):101-112

The activity and stability of Chromobacterium viscosum lipase (glycerolester hydrolase, EC 3.1.1.3)-catalyzed olive oil hydrolysis in sodium bis (2-ethyl-1-hexyl)sulfosuccinate (AOT)/isooctane reverse micelles is increased appreciably when low molecular weight polyethylene glycol (PEG 400) is added to the reverse micelles. To understand the effect of PEG 400 on the phase behavior of the reverse micellar system, the phase diagram of AOT/PEG 400/water/isooctane system was studied. The influences of relevant parameters on the catalytic activity in AOT/PEG 400 reverse micelles were investigated and compared with the results in the simple AOT reverse micelles. In the presence of PEG 400, the linear decreasing trend of the lipase activity with AOT concentration, which is observed in the simple AOT reverse micelles, disappeared. Enzyme entrapped in AOT/PEG reverse micelles was very stable, retaining>75% of its initial activity after 60 d, whereas the half-life in simple AOT reverse micelles was 38 d. The kinetics parameter maximum velocity (V _max)exhibiting the temperature dependence and the activation energy obtained by Arrhenius plot was suppressed significantly by the addition of PEG 400.     

109.

Cyclic esters of aliphatic diacids with pyrocatechol and hydroquinone     

Volker Böhmer  Friedhelm Schneider  Keiichi Fukuyama  Shigeo Fujii 《Monatshefte für Chemie / Chemical Monthly》1985,116(12):1419-1432

Cyclic esters of adipic acid, suberic acid and sebacic acid were prepared by reaction of the acid dichlorides and pyrocatechol or hydroquinone in benzene under high dilution conditions. While only the cyclic dimers could be obtained from hydroquinone, pyrocatechol formed cyclic monomers as well as cyclic dimers (and also a cyclic dimer with succinic acid). The structure of all compounds was confirmed by¹H-NMR- and mass spectra. The crystal structures of the pyrocatechol esters were determined by single crystal X-ray analysis.

---

Cyclische Ester aliphatischer Dicarbonsäuren mit Brenzcatechin und Hydrochinon

Zusammenfassung Es wurden cyclische Ester von Adipinsäure, Korksäure und Sebacinsäure durch Reaktion der entsprechenden Säure-Dichloride mit Brenzcatechin oder Hydrochinon bei hoher Verdünnung hergestellt. Während mit Hydrochinon lediglich die cyclischen Dimeren erhalten werden konnten, wurden mit Brenzcatechin sowohl cyclische Monomere als auch cyclische Dimere erhalten (ebenfalls das cyclische Dimer mit Bernsteinsäure). Die Strukturen wurden mittels¹H-NMR und Massenspektren gesichert. Die Kristallstrukturen der Brenzcatechin-Ester wurden mittels Röntgenstrukturanalyse bestimmt.

     

110.

Module-based assembly of copper(II) chloranilate compounds: syntheses, crystal structures, and magnetic properties of [[Cu(2)(CA)(terpy)(2)][Cu(CA)(2)]](n)() and [[Cu(2)(CA)(terpy)(2)(dmso)(2)][Cu(CA)(2)(dmso)(2)](EtOH)](n)(H(2)CA = chloranilic acid, terpy = 2,2':6',2' '-terpyridine, dmso = dimethyl sulfoxide)     

Kawahara M  Kabir MK  Yamada K  Adachi K  Kumagai H  Narumi Y  Kindo K  Kitagawa S  Kawata S 《Inorganic chemistry》2004,43(1):92-100

Two new copper(II) compounds of chloranilate and 2,2':6',2' '-terpyridine have been synthesized, and the structures have been solved by the single-crystal X-ray diffraction method. The crystal structure of [[Cu(2)(CA)(terpy)(2)][Cu(CA)(2)]](n)(1), where H(2)CA = chloranilic acid and terpy = 2,2':6',2' '-terpyridine, consists of two modules, the dimer unit [Cu(2)(CA)(terpy)(2)](2+) and the anionic mononuclear unit [Cu(CA)(2)](2)(-), forming an alternated chain. The chain is stabilized by semicoordinating and additional but efficient secondary bonding interactions. The crystal structure of [[Cu(2)(CA)(terpy)(2)(dmso)(2)][Cu(CA)(2)(dmso)(2)](EtOH)](n)(2), where dmso = dimethyl sulfoxide, consists of solvent molecules and two discrete modules, the dimer unit [Cu(2)(CA)(terpy)(2)(dmso)(2)](2+) and the anionic mononuclear unit [Cu(CA)(2)(dmso)(2)](2)(-). The dimer units form a layer by secondary bonding interactions, and the monomer units and ethanol molecules are introduced between the layers. The magnetic properties of 1 and 2 have been investigated in the temperature range 2.0-300 K. A weak ferromagnetic interaction was observed in 1, J(a) = 2.36 cm(-)(1) and zJ(b) = -0.68 cm(-)(1) while no exchange coupling was observed in 2.     

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		CD379Br		CD381Br
$\text{ν}{}_2$		991.396 82 (18)		991.388 46 (17)		cm?1
$\text{ν}{}_5$		1055.469 00 (12)		1055.466 32 (12)		cm?1
$\text{μ}{}_0$		1.830 42 (52)		1.829 84 (47)		D
$\text{μ}{}_2$		1.829 93 (48)		1.829 57 (46)		D
$\text{μ}{}_5$		1.832 23 (60)		1.831 19 (56)		D

A stannylene strategy for regioselective acylation and phosphorylation of 1,2-cyclohexylidene-myo-inositol. Its convenient resolution and phosphatidylinositol synthesis

The bis(dibutylstannylene) derivative of 1,2-cyclohexylidene-myo-inositol reacted with (S)-O-acetylmandeloyl chloride and diphosphate tetraesters to give 3,6-dimandelate and 3-phosphate, respectively. Using the stannylene methodology for the optical resolution and regioselective phosphorylation of the ketal, a concise synthesis of phosphatidylinositol with the natural configuration was accomplished.     

Preparation and characterization of high-specific-surface-area activated carbons from K2CO3-treated waste polyurethane

An activated carbon with high specific surface area was prepared from polyurethane foam by chemical activation with K2CO3 and the influences of carbonization temperature and impregnation ratio on the pore structure of the prepared activated carbon were investigated. It was found that the specific surface area of the activated carbon was at a maximum value (about 2800 m(2)/g) at a carbonization temperature of 1073 K and at an impregnation ratio of 1.0. It was concluded that the polyurethane foam structure was modified during impregnation by K2CO3, K2CO3 promoted charring during carbonization, and then the weight loss behavior was changed below 700 and above 1000 K, carbon in the char was consumed by K2CO3 reduction, and this led to the high specific surface area. The prepared activated carbon had a very sharp micropore size distribution, compared with the commercial activated carbon having high specific surface area. The amounts of three organic vapors (benzene, acetone, and octane) adsorbed on the prepared activated carbons was much larger than those on the traditional coconut shell AC and the same as those on the commercial activated carbon except for octane. We surmised that the high specific surface area was due to the modification of the carbonization behavior of polyurethane foam by K2CO3.     

Radiation-induced solid-state polymerization of trioxane under high pressure

The in-source polymerization of trioxane in the solid state was investigated over a wide range of temperature and pressure, i.e., from 30 to 140°C and up to 7000 kg/cm², respectively. In the polymerization that was carried out slightly below the melting point under pressure, the higher the pressure, the higher the rate of polymerization. It was confirmed that the maximum rate of solid-state polymerization of trioxane occurs near the melting points, even under elevated pressure. The rate of polymerization decreased with increasing pressure at constant temperature. The shape of the time–conversion curves may be classified into two types, i.e., one which is typical of high pressure and low temperature, and the other which is typical of low pressure and high temperature. Changes in the shape of the conversion—intrinsic viscosity curves occurred coincidentally. Thus, three regions for the different “polymerization characteristic” were determined as functions of polymerization temperature and pressure. Explanations are given for the above-mentioned polymerization characteristic.     

Catalytic direct 1,4-conjugate addition of aldehydes to vinylketones on secondary-amines immobilised in FSM-16 silica

Direct 1,4-conjugate addition of naked aldehydes to vinylketones is catalysed effectively by N-methyl-3-aminopropylated FSM-16 mesoporous silica, which can be regarded as a novel heterogeneous catalysis for a practical C-C bond formation reaction.     

Comparative characterization study of microporous carbons by HRTEM image analysis and gas adsorption

The present work presents a useful comparison of micropore size distributions (MPSDs) obtained from gas adsorption and image analysis of high-resolution transmission electron micrographs. It is shown that the MPSD obtained for a chemical activated carbon is concordant with that obtained from CO2 adsorption. In addition, this technique has allowed us to obtain the MPSD of a carbon molecular sieve (CMS) prepared in our laboratory by a copyrolysis process, which could only be characterized by CO2 adsorption at 273 K (not by N2 adsorption at 77 K due to diffusional problems). The MPSD obtained by high-resolution transmission electron microscopy (HRTEM) for the CMS is wider than that obtained by CO2 adsorption, suggesting that HRTEM is detecting the closed porosity existing in this sample, which is not accessible to gas adsorption. The existence of closed porosity in the CMS is explained considering the preparation method used. Thus, HRTEM combined with image analysis seems to be useful for structural analysis of narrow micropores including closed porosity.     

Improvement in enzyme activity and stability by addition of low molecular weight polyethylene glycol to sodium bis(2-ethyl-L-hexyl)sulfosuccinate/isooctane reverse micellar system

The activity and stability of Chromobacterium viscosum lipase (glycerolester hydrolase, EC 3.1.1.3)-catalyzed olive oil hydrolysis in sodium bis (2-ethyl-1-hexyl)sulfosuccinate (AOT)/isooctane reverse micelles is increased appreciably when low molecular weight polyethylene glycol (PEG 400) is added to the reverse micelles. To understand the effect of PEG 400 on the phase behavior of the reverse micellar system, the phase diagram of AOT/PEG 400/water/isooctane system was studied. The influences of relevant parameters on the catalytic activity in AOT/PEG 400 reverse micelles were investigated and compared with the results in the simple AOT reverse micelles. In the presence of PEG 400, the linear decreasing trend of the lipase activity with AOT concentration, which is observed in the simple AOT reverse micelles, disappeared. Enzyme entrapped in AOT/PEG reverse micelles was very stable, retaining>75% of its initial activity after 60 d, whereas the half-life in simple AOT reverse micelles was 38 d. The kinetics parameter maximum velocity (V _max)exhibiting the temperature dependence and the activation energy obtained by Arrhenius plot was suppressed significantly by the addition of PEG 400.     

Cyclic esters of aliphatic diacids with pyrocatechol and hydroquinone

Cyclic esters of adipic acid, suberic acid and sebacic acid were prepared by reaction of the acid dichlorides and pyrocatechol or hydroquinone in benzene under high dilution conditions. While only the cyclic dimers could be obtained from hydroquinone, pyrocatechol formed cyclic monomers as well as cyclic dimers (and also a cyclic dimer with succinic acid). The structure of all compounds was confirmed by¹H-NMR- and mass spectra. The crystal structures of the pyrocatechol esters were determined by single crystal X-ray analysis.

---

Cyclische Ester aliphatischer Dicarbonsäuren mit Brenzcatechin und Hydrochinon

Zusammenfassung Es wurden cyclische Ester von Adipinsäure, Korksäure und Sebacinsäure durch Reaktion der entsprechenden Säure-Dichloride mit Brenzcatechin oder Hydrochinon bei hoher Verdünnung hergestellt. Während mit Hydrochinon lediglich die cyclischen Dimeren erhalten werden konnten, wurden mit Brenzcatechin sowohl cyclische Monomere als auch cyclische Dimere erhalten (ebenfalls das cyclische Dimer mit Bernsteinsäure). Die Strukturen wurden mittels¹H-NMR und Massenspektren gesichert. Die Kristallstrukturen der Brenzcatechin-Ester wurden mittels Röntgenstrukturanalyse bestimmt.

     

Module-based assembly of copper(II) chloranilate compounds: syntheses, crystal structures, and magnetic properties of [[Cu(2)(CA)(terpy)(2)][Cu(CA)(2)]](n)() and [[Cu(2)(CA)(terpy)(2)(dmso)(2)][Cu(CA)(2)(dmso)(2)](EtOH)](n)(H(2)CA = chloranilic acid, terpy = 2,2':6',2' '-terpyridine, dmso = dimethyl sulfoxide)

Two new copper(II) compounds of chloranilate and 2,2':6',2' '-terpyridine have been synthesized, and the structures have been solved by the single-crystal X-ray diffraction method. The crystal structure of [[Cu(2)(CA)(terpy)(2)][Cu(CA)(2)]](n)(1), where H(2)CA = chloranilic acid and terpy = 2,2':6',2' '-terpyridine, consists of two modules, the dimer unit [Cu(2)(CA)(terpy)(2)](2+) and the anionic mononuclear unit [Cu(CA)(2)](2)(-), forming an alternated chain. The chain is stabilized by semicoordinating and additional but efficient secondary bonding interactions. The crystal structure of [[Cu(2)(CA)(terpy)(2)(dmso)(2)][Cu(CA)(2)(dmso)(2)](EtOH)](n)(2), where dmso = dimethyl sulfoxide, consists of solvent molecules and two discrete modules, the dimer unit [Cu(2)(CA)(terpy)(2)(dmso)(2)](2+) and the anionic mononuclear unit [Cu(CA)(2)(dmso)(2)](2)(-). The dimer units form a layer by secondary bonding interactions, and the monomer units and ethanol molecules are introduced between the layers. The magnetic properties of 1 and 2 have been investigated in the temperature range 2.0-300 K. A weak ferromagnetic interaction was observed in 1, J(a) = 2.36 cm(-)(1) and zJ(b) = -0.68 cm(-)(1) while no exchange coupling was observed in 2.