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| 1.
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Segi, Masahito ; Kawai, Katsuhiko ; Honda, Mitsunori ; Fujinami, Shuhei
概要:
金沢大学大学院自然科学研究科物質創成<br />金沢大学工学部<br />Stereoselective hetero Diels-Alder reaction of selenoaldehydes, generated by therma
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l retro Diels-Alder reaction of anthracene cycloadducts, with pentavalent 3,4-dimethylphosphole chalcogenides at 110 °C in toluene to give the corresponding [4+2] cycloadducts as a single diastereoisomer in good yields, accompanied by a slight scrambling of chalcogen atoms. Higher reaction temperature led to an increase of the scrambling between chalcogen atoms. © 2007 Elsevier Ltd. All rights reserved.
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| 2.
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Taniguchi, Kazutaka ; Okumura, Hisako ; Honda, Mitsunori ; Suda, Mitsuhiro ; Fujinami, Shuhei ; Kuwae, Akio ; Hanai, Kazuhiko ; Maeda, Shiro ; Kunimoto, Ko-Ki
概要:
金沢大学理工研究域物質化学系<br />The crystal structure of a new polymorph of 1-acetyl-2-thiohydantoin has been determined by X-ray di
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ffraction. The crystal, C5H6N2O2S, belongs to space group P1 with cell dimensions of a = 4.9865(7)Å, b = 5.5716(7)Å, c = 12.544(2)Å, a = 74.793(8)°, b = 80.413(9)°, g = 85.001(10)°. The final R1 value is 0.036 for 1304 reflections (I > 2.0s(I)). In the new polymorph, intermolecular hydrogen bonds are formed between the acetyl C=O and the amide N-H groups [N(1)·O(2)(i) 2.800(2)Å, N(1)-H·O(2)(i) 151.02o, symmetry codes: (i) x+1, y-1, z] to form an infinite chain structure. On the other hand, the hydrogen bonds in the known form are formed between the amide C=O and the amide N-H groups of the thiohydantoin rings. 2009 © The Japan Society for Analytical Chemistry.
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| 3.
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Ogawa, Toshikazu ; Okumura, Hisako ; Honda, Mitsunori ; Suda, Mitsuhiro ; Fujinami, Shuhei ; Kuwae, Akio ; Hanai, Kazuhiko ; Kunimoto, Ko-Ki
概要:
金沢大学理工研究域物質化学系<br />A new polymorphic crystal of the title compound, C3H4N2OS, belongs to space group P1 with cell dimen
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sions of a = 4.0520(9)Å, b = 6.550(1)Å, c = 9.170(2)Å, a = 100.148(4)°, b = 100.814(4)°, g = 96.831(4)°, R1= 0.069. Neighboring molecules are connected to form cyclic dimers via two types of hydrogen bonds, one between the thioamide groups and the other between the amide moieties, showing a distinctive difference from the hydrogen-bonding pattern of the known form. 2009 © The Japan Society for Analytical Chemistry.
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| 4.
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Sakai, Hiroki ; Ding, Xia ; Yoshida, Tetsusuke ; Fujinami, Shuhei ; Ukaji, Yutaka ; Inomata, Katsuhiko
概要:
金沢大学金沢大学理工研究域物質化学系<br />The regio- and enantioselective hetero Diels-Alder reaction of a nitroso compound with a cyclic
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dienol, cyclohexa-1,3-dienylmethanol, has been realized utilizing stoichiometric amount of tartaric acid ester as a chiral auxiliary to afford the corresponding dihydro-1,2-oxazine with complete regioselectivity and high enantioselectivity of up to 92% ee. A catalytic version of the asymmetric hetero Diels-Alder reaction of nitroso compounds with the dienol was also achieved to afford the corresponding optically active cycloadducts with up to 83% ee. The addition of MS 4A was crucial to realize reproducible high enantioselectivity. © 2008 The Japan Institute of Heterocyclic Chemistry All rights reserved.
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| 5.
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Osawa, Kunitoyo ; Furutachi, Hideki ; Fujinami, Shuhei ; Suzuki, Masatatsu
概要:
金沢大学理学部<br />金沢大学大学院自然科学研究科物質創成<br />The title complex, trans,trans,trans-[FeII(C10H 6NO2)2-(C2H6O) 2], is centrosymmetr
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ic and the quinaldinate ligands form five-membered chelate rings. The geometry of the complex is distorted octahedral, with a trans-FeN2O4 chromophore. The hydroxy H atom forms an intermolecular hydrogen bond with the carbonyl O atom of the quinaldinate ligand. © 2003 International Union of Crystallography Printed in Great Britain - all rights reserved.
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| 6.
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Serizawa, Masakazu ; Fujinami, Shuhei ; Ukaji, Yutaka ; Inomata, Katsuhiko
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金沢大学理工研究域物質化学系<br />The asymmetric addition of alkynylzinc reagents, prepared in situ from dimethylzinc and 1-alkynes, t
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o α-dinitrones derived from glyoxal and N-(4-isopropylbenzyl)hydroxylamine was investigated by utilizing dicyclohexyl (R,R)-tartrate as a chiral auxiliary. The addition reaction of methyl(2-phenylethynyl)zinc afforded the corresponding optically active C2-symmetric (R,R)-bis(hydroxylamine) derivative with enantioselectivities of 90% and 81% ee by utilizing a stoichiometric and catalytic amount of the tartrate, respectively. Furthermore, the catalytic addition reaction of several alkynylzinc reagents also furnished the corresponding bis(hydroxylamine) with moderate to good enantioselectivities. © 2008 Elsevier Ltd. All rights reserved.
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| 7.
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Yoshida, Mari ; Sassa, Naotaro ; Kato, Tomomitsu ; Fujinami, Shuhei ; Soeta, Takahiro ; Inomata, Katsuhiko ; Ukaji, Yutaka
概要:
Desymmetrization of the divinyl carbinol 1,4-pentadien-3-ol was accomplished by the asymmetric 1,3-dipolar cycloaddition
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of azomethine imines based on a magnesium-mediated, multinucleating chiral reaction system utilizing diisopropyl (R,R)-tartrate as the chiral auxiliary. The corresponding optically active trans-pyrazolidines, each with three contiguous stereogenic centers, were obtained with excellent regio-, diastereo-, and enantioselectivity, with results as high as 99%ee. This reaction was shown to be applicable to both aryl- and alkyl-substituted azomethine imines. The use of a catalytic amount of diisopropyl (R,R)-tartrate was also effective when accompanied by the addition of MgBr2. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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| 8.
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Miyamoto, Yoshiaki ; Wada, Norihiro ; Soeta, Takahiro ; Fujinami, Shuhei ; Inomata, Katsuhiko ; Ukaji, Yutaka
概要:
The stereoselective direct transformation of N-(propargylic)hydroxylamines into cis-2-acylaziridines was achieved by the
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combined use of AgBF4 and CuCl. Copper salts were found to promote the transformation of the intermediary 4-isoxazolines into 2-acylaziridines and both 3-aryl- and 3-alkyl-substituted 2-acylaziridines could be prepared by using this method. Furthermore, subsequent 1,3-dipolar cycloaddition of azomethine ylides that were generated in situ from the intermediary 2-acylaziridines with maleimides was achieved in a stereoselective one-pot procedure to afford the corresponding 2-acylpyrrolidines, which consisted of an octahydropyrrolo[3,4-c]pyrrole skeleton. Love the way ylide: The transformation of N-(propargylic) hydroxylamines into cis-2-acylaziridines and subsequent 1,3-dipolar cycloaddition of the in situ generated azomethine ylides with maleimides stereoselectively afforded 2-acylpyrrolidines. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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| 9.
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Sakai, Takahiro ; Soeta, Takahiro ; Endo, Kohei ; Fujinami, Shuhei ; Ukaji, Yutaka
概要:
An asymmetric Strecker-type reaction of nitrones using acetone cyanohydrin as a source of HCN has been realized. A magne
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sium-tartramide complex, generated from (R,R)-2,3-dihydroxy-1,4-di(pyrrolidin-1-yl)-butane-1,4-dione and MeMgBr, promoted transcyanation from the bromomagnesium salt of the cyanohydrin, in the presence of a catalytic amount of DBU, to afford the corresponding optically active (S)-α-amino nitrile derivatives. The reaction was applicable to various nitrones giving high-to-excellent enantioselectivities. © 2013 American Chemical Society.
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| 10.
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Yoshida, Mari ; Sassa, Naotaro ; Kato, Tomomitsu ; Fujinami, Shuhei ; Soeta, Takahiro ; Inomata, Katsuhiko ; Ukaji, Yutaka
概要:
Desymmetrization of the divinyl carbinol 1,4-pentadien-3-ol was accomplished by the asymmetric 1,3-dipolar cycloaddition
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of azomethine imines based on a magnesium-mediated, multinucleating chiral reaction system utilizing diisopropyl (R,R)-tartrate as the chiral auxiliary. The corresponding optically active trans-pyrazolidines, each with three contiguous stereogenic centers, were obtained with excellent regio-, diastereo-, and enantioselectivity, with results as high as 99 %ee. This reaction was shown to be applicable to both aryl- and alkyl-substituted azomethine imines. The use of a catalytic amount of diisopropyl (R,R)-tartrate was also effective when accompanied by the addition of MgBr2. © 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
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| 11.
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Nishiyama, Kaori ; Kamiya, Ayumi ; Hammam, Mostafa A. S. ; Kinoshita, Hideki ; Fujinami, Shuhei ; Ukaji, Yutaka ; Inomata, Katsuhiko
概要:
Total syntheses of sterically locked phycocyanobilin derivatives with a 15Z-anti or a 15E-anti CD-ring component were performed toward elucidation of the stereochemistry and function of the chromophore in phytochromes. In the course
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of the construction of a sterically locked 15E-anti CD-ring component employing 5-tosylpyrrolin-2-one derivatives as the D-ring, the Ts group was found to be rearranged under acidic conditions to give a mixture of regioisomers, both of which could be transformed into the same CD-ring precursor via detosylation with a base followed by Wittig-like coupling reaction. In addition, a sterically locked 15E-anti biliverdin derivative was also synthesized. Total syntheses of sterically locked phycocyanobilin derivatives bearing a 15Z-anti or a 15E-anti CD-ring component were performed towards elucidation of the stereochemistry and function of the chromophore in phytochromes.
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| 12.
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Komiyama, Kazuya ; Furutachi, Hideki ; Nagatomo, Shigenori ; Hashimoto, Akifumi ; Hayashi, Hideki ; Fujinami, Shuhei ; Suzuki, Masatatsu ; Kitagawa, Teizo
概要:
Oxygenation of copper(I) with tetradentate tripodal ligands (L) comprised of a tris(aminoethyl)amine (tren) skeleton hav
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ing sterically bulky substituent(s) on the terminal nitrogens has been investigated, where L = tris(N-benzylaminoethyl)amine (LH,Bn), tris(N-benzyl-N-methylaminoethyl)amine (LMe,Bn), or tris(N,N-dimethylaminoethyl)amine (LMe,Me). All the copper(I) complexes reacted with dioxygen at low temperatures to produce superoxocopper(II) and/or trans-(μ-1,2-peroxo)-dicopper(II) complexes depending on the steric bulkiness of the terminal nitrogens and the reaction conditions. The reaction of a copper(I) complex [Cu(LH,Bn)]+ at −90 °C in acetone resulted in the formation of a superoxo complex [Cu(LH,Bn)(O2)]+ as a less stable species and a peroxo complex [{Cu(LH,Bn)}2(O2)]2+ as a stable species. The structures of [Cu(LH,Bn)]ClO4 and [{Cu(LH,Bn)}2(O2)](BPh4)2·8(CH3)2CO were determined by X-ray crystallography. [{Cu(LH,Bn)}2(O2)]2+ has a trans-(μ-1,2-peroxo)-dicopper(II) core with a trigonal bipyramidal structure. The O–O bond distance is 1.450(5) Å with an intermetallic Cu···Cu separation of 4.476(2) Å. The resonance Raman spectrum of [{Cu(LH,Bn)}2(O2)]2+ measured at −90 °C in acetone-d6 showed a broad ν(O–O) band at 837–834 cm−1 (788 cm−1 for an 18O labeled sample) and two ν(Cu–O) bands at 556 and 539 cm−1, suggesting the presence of two peroxo species in solution. [Cu(LMe,Bn)]+ also produced both superoxo and trans-μ-1,2-peroxo species, [Cu(LMe,Bn)(O2)]+ and [{Cu(LMe,Bn)}2(O2)]2+. At a lower concentration of [Cu(LMe,Bn)]+ (∼0.24 mM) and higher dioxygen concentration (P(O2) = ∼1 atm), the superoxo species is predominantly formed, whereas at a higher concentration of [Cu(LMe,Bn)]+ (∼1 mM) and lower dioxygen concentration (P(O2) = ∼0.02 atm) the formation of the peroxo species is observed. The resonance Raman spectrum of [Cu(LMe,Bn)(O2)]+ (∼1 mM) in acetone-d6 at ∼−95 °C exhibited a ν(O–O) band at 1120 cm−1 (1059 cm−1 for an 18O labeled sample) and that of [{Cu(LMe,Bn)}2(O2)]2+ (∼3 mM) in acetone-d6 at ∼−90 °C showed two ν(O–O) bands at 812 and 797 cm−1 (767 and 753 cm−1 for an 18O labeled sample), respectively. A similar observation was also made for [{Cu(LMe,Me)}2(O2)]2+. Relationships between the energies of the LMCT and d–d transitions and those of the ν(O–O) and ν(Cu–O) stretching vibrations and the steric constraints in the Cu(II)–(O22−)–Cu(II) core are discussed.
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| 13.
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Sugimoto, Hideki ; Nagayama, Toshihiko ; Maruyama, Sachihito ; Fujinami, Shuhei ; Yasuda, Yuichi ; Suzuki, Masatatsu ; Uehara, Akira
概要:
A new dinucleating ligand containing a sterically bulky imidazolyl group, Ph-Htidp (N,N,N′,N′-tetrakis[(1-methyl-4,5-dip
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henyl-2-imidazolyl)methyl]-1,3-diamino-2-propanol), and its μ-alkoxo-diiron(II) complexes [Fe2(Ph-tidp)(RCO2)](ClO4)2, (RCO2 = C6H5CO2 (1), C6F5CO2 (2), CF3CO2 (3), and C2H5CO2 (4)), were synthesized. The structure of complex 1 was determined by X-ray crystallography. Complex 1 crystallizes in the monoclinic space group P21/c with a = 13.464(2), b = 19.223(4), c = 31.358(4) Å, β = 92.84(2)°, and Z = 4. The complex has a doubly-bridged structure with μ-alkoxo of Ph-tidp and μ-benzoate; the two iron centers have a distorted five-coordinate structure with N3O2 donor set. All the complexes showed fairly good reversible oxygenation below −30 °C in CH2Cl2, which was monitored by UV-vis and NMR spectroscopies, and dioxygen up-take measurements. Introduction of 4,5-diphenyl substituents into 2-imidazolyl group stabilized the μ-peroxo diiron species against irreversible oxidation, just as introduction of 6-methyl substituent into 2-pyridyl group did. Phenyl substituents appear to weaken the electron donor ability of a dinucleating ligand to stabilize divalent oxidation state of iron and to form a hydrophobic cavity for a O2 binding site, which would suppress the irreversible oxidation and facilitate the reversible oxygenation. Dioxygen affinities of the Ph-tidp and Me4-tpdp diiron(II), and the tpdp and bpmp dicobalt(II) complexes were measured, [Fe2(Me4-tpdp)(RCO2)]2+ (RCO2 = C6H5CO2 and RCO2 = CF3CO2) and [Co2(L)(RCO2)]2+ (L = tpdp, RCO2 = CH3CO2, and L = bpmp, RCO2 = C6F5CO2, and CF3CO2), where Me4-tpdp, tpdp, and bpmp are N,N,N′,N′-tetrakis[(6-methyl-2-pyridyl)methyl]-1,3-diamino-2-propanolate, N,N,N′,N′-tetrakis(2-pyridylmethyl)-1,3-diamino-2-propanolate, and 2,6-bis[bis(2-pyridylmethyl)aminomethyl]-4-methylphenolate, respectively. Within a series of the Ph-tidp diiron(II) complexes, dioxygen affinity is well correlated with electron donor ability of bridging carboxylates (1 (C6H5CO2) > 2 (C6F5CO2) > 3 (CF3CO2)). In contrast to the above trend, dioxygen affinities of the Ph-tidp complexes are lower than those of the Me4-tpdp complexes, although electron donor abilities of the Me4-tpdp complexes are weaker than those of the Ph-tidp complexes. Significant enhancement of dioxygen affinity was observed for both iron and cobalt complexes with 2,6-bis(aminomethyl)phenolate bridging skeleton compared to the complexes with a 1,3-diamino-2-propanolate bridging one. Thermodynamic study suggested that the observed enhancement is mainly attributable to a favorable entropy effect along with a steric effect.
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| 14.
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Yonezawa, Yasushi ; Furuya, Tomoki ; Aratani, Takahiro ; Fujinami, Shuhei ; Inomata, Katsuhiko ; Ukaji, Yutaka
概要:
Desymmetrization of various meso-methylenecyclopropanes was accomplished by a palladium-catalyzed asymmetric ring-openin
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g bis(alkoxycarbonylation) reaction employing a chiral bioxazoline ligand. The reaction proceeded smoothly in the presence of copper(I) triflate under carbon monoxide and oxygen at ambient pressure to give the corresponding optically active α-methyleneglutarates with up to 60% ee. Desymmetrization of protected meso-(3-methylenecyclopropane- 1,2-diyl)dimethanols was also carried out to give enantioenriched highly oxygen-functionalized α-methyleneglutarates. © 2014 Elsevier Ltd. All rights reserved.
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| 15.
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Sakai, Hiroki ; Ding, Xia ; Yoshida, Tetsusuke ; Fujinami, Shuhei ; Ukaji, Yutaka ; Inomata, Katsuhiko
概要:
金沢大学金沢大学理工研究域物質化学系<br />The regio- and enantioselective hetero Diels-Alder reaction of a nitroso compound with a cyclic
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dienol, cyclohexa-1,3-dienylmethanol, has been realized utilizing stoichiometric amount of tartaric acid ester as a chiral auxiliary to afford the corresponding dihydro-1,2-oxazine with complete regioselectivity and high enantioselectivity of up to 92% ee. A catalytic version of the asymmetric hetero Diels-Alder reaction of nitroso compounds with the dienol was also achieved to afford the corresponding optically active cycloadducts with up to 83% ee. The addition of MS 4A was crucial to realize reproducible high enantioselectivity. © 2008 The Japan Institute of Heterocyclic Chemistry All rights reserved.
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| 16.
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Sakata, Ryo ; Iwamoto, Ryoji ; Fujinami, Shuhei ; Ukaji, Yutaka ; Inomata, Katsuhiko
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金沢大学理工研究域物質化学系<br />t-Butyl 3,4-dialkyl-1H-pyrrole-2-carboxylates were oxidized with ochloranil in the presence of MeOH
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to afford the corresponding 5-methoxypyrrolin-2-one derivatives. The resulting 5-methoxypyrrolin-2-one was reacted with various nucleophiles under acidic conditions to afford the functionalized pyrrolinone derivatives in good yields. © The Japan Institute of Heterocyclic Chemistry.
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| 17.
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Kazama, Hideyuki ; Fujinami, Shuhei ; Sado, Akira
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| 18.
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Ogata, Yoichi ; Fujinami, Shuhei ; Shibata, Muraji
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