Papers - DANJO Hiroshi
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Assembly Modulation by Adjusting Countercharges of Heterobimetallic Supramolecular Polymers Composed of Tris(spiroborate) Twin Bowls Reviewed
Hiroshi Danjo, Kadzuya Hirata, Masanori Noda, Susumu Uchiyama, Kiichi Fukui, Masatoshi Kawahata, Isao Azumaya, Kentaro Yamaguchi, Toshifumi Miyazawa
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY 132 ( 44 ) 15556 - 15558 2010.10
Joint Work
Authorship：Lead author, Corresponding author Publisher：AMER CHEMICAL SOC
Heterobimetallic supramolecular polymers were prepared by treatment of the supramolecular polymers composed of tris(spiroborate) type molecular connecting modules with a potassium cation. On the other hand, the addition of a barium cation led to dissociation of the supramolecular polymer chain. Modulation of polymer formation was realized by the use of small metal cations as a control factor.
DOI： 10.1021/ja1084964
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Ionic probe attachment ionization mass spectrometry Reviewed
Fumihiro Ito, Tomoko Nakamura, Satoko Yorita, Hiroshi Danjo, Kentaro Yamaguchi
TETRAHEDRON LETTERS 50 ( 46 ) 6252 - 6255 2009.9
Joint Work
Publisher：PERGAMON-ELSEVIER SCIENCE LTD
A new ionization method that uses metal-complex-based ionization probes containing the 2,6-bis(oxazolinyl)pyridine (pybox) ligand is presented. This method was proven to effectively ionize large complex molecules, including biomolecules. The preparation of the charged probes and their application to the ionization of biomolecules using cold-spray ionization mass spectrometry are shown. (C) 2009 Elsevier Ltd. All rights reserved.
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SYNTHESIS OF OPTICALLY ACTIVE P-CHIROGENIC FERROCENE-FUSED BENZOPHOSPHOLE BY DIASTEREOSELECTIVE INTRAMOLECULAR CYCLIZATION OF PHOSPHANYLFERROCENE DERIVATIVES Reviewed
Shuji Yasuike, Jun-ichi Hagiwara, Hiroshi Danjo, Masatoshi Kawahata, Naoki Kakusawa, Kentaro Yamaguchi, Jyoji Kurita
HETEROCYCLES 78 ( 12 ) 3001 - 3010 2009.7
Joint Work
Publisher：PERGAMON-ELSEVIER SCIENCE LTD
A novel optically active P-chirogenic ferrocene-fused benzophosphole, (S(Fc),R(P))-4-phenylbenzo[b]ferroceno[d]phosphole, was synthesized by diastereoselective intramolecular cyclization of (S(Fc))-1-(diphenylphosphanyl)2-(2-lithiophenyl)ferrocene intermediates in two routes. The geometry of the new P-chirogenic ferrocenophosphole including absolute configuration of the phosphorous was disclosed by single crystal X-ray analysis of the palladium complex derived from the reaction of the phosphole with di-mu-dichloro-bis{2-[(dimethylamino)methyl]phenyl-C(1),N}dipalladium (II).
DOI： 10.3987/COM-09-11812
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Back to Back Twin Bowls of D-3-Symmetric Tris(spiroborate)s for Supramolecular Chain Structures Reviewed
Hiroshi Danjo, Kadzuya Hirata, Seiki Yoshigai, Isao Azumaya, Kentaro Yamaguchi
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY 131 ( 131 ) 1638 - 1639 2009.2
Joint Work
Authorship：Lead author, Corresponding author Publisher：AMER CHEMICAL SOC
A new class of D-3-symmetric tris(spiroborate) cyclophanes has been designed and prepared for the construction of supramolecular chain structures by iterative host-guest interaction with ditopic guest molecules. The treatment of these compounds with [Ir(tpy)(2)](PF6)(3) complex in solution led to the formation of the chain structure, which was confirmed by H-1 NMR and CSI-MS studies. The chain structure exhibited rapid temperature-responsive gelation behavior in their HMPA solution.
DOI： 10.1021/ja8071435
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Construction of optically active multimetallic systems of rhodium(I), palladium(II), and ruthenium(II) with a P-chiral tetraphosphine ligand Reviewed
Keiji Yashio, Masatoshi Kawahata, Hiroshi Danjo, Kentaro Yamaguchi, Masaharu Nakamura, Tsuneo Imamoto
JOURNAL OF ORGANOMETALLIC CHEMISTRY 694 ( 694 ) 97 - 102 2008.10
Joint Work
Publisher：ELSEVIER SCIENCE SA
The treatment of optically P-chiral tetraphosphine, (3S, 6R, 9R, 12S)-6,9-di-tert-butyl-2,2,3,12,13,13-hexamethyl3,6,9,12-tetraphosphatetradecane (1), with rhodium(I), palladium(II), and ruthenium( II) complex precursors led to the selective formation of mono-, di-, or trinuclear homo- or heterometallic complexes, [Rh(1)]SbF6 (4), [{Rh(nbd)}(2)(1)](SbF6)(2) (3), [{Pd(eta(3)-allyl)} 2(1)](SbF6)(2) (5), [{RuCl(eta(5)-C-5(CH3)(5))}(2)(1)] (6), and [{RuCl2(eta(6)-benzene)}(2)(PdCl2)(1)] (8). These complexes were characterized by NMR and X-ray crystallographic analysis. (C) 2008 Elsevier B. V. All rights reserved.
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Formation of 1,4-diphosphinobenzenes via tele-substitution on fluorobenzenechromium complexes Reviewed
Yoshikazu Yamamoto, Hiroshi Danjo, Kentaro Yamaguchi, Tsuneo Imamoto
JOURNAL OF ORGANOMETALLIC CHEMISTRY 693 ( 693 ) 3546 - 3552 2008.8
Joint Work
Publisher：ELSEVIER SCIENCE SA
The meta-tele-substitution of 2-(boranatophosphino) fluorobenzenechromium complexes took place with various lithiated secondary phosphine-boranes as nucleophiles to give para-substituted bis(boranatophosphino) benzenechromiums. It was revealed that the yield of the tele-substitution product was strongly affected by the strength of a proton acid. Isotope labeling experiments indicated that 1,5-hydrogen migration was involved in this transformation. (C) 2008 Elsevier B.V. All rights reserved.
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Catalytic activities of Pd-tailored single wall carbon nanohorns Reviewed
Tsutomu Itoh, Hiroshi Danjo, Wataru Sasaki, Koki Urita, Elena Bekyarova, Miki Arai, Tsuneo Imamoto, Masako Yudasaka, Sumio Iijima, Hirofumi Kanoh, Katsumi Kaneko
CARBON 46 ( 46 ) 172 - 175 2007.11
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Facile synthesis of highly congested 1,2-diphosphinobenzenes from bis(phosphine)boronium salts Reviewed
Yoshikazu Yamamoto, Toru Koizumi, Kosuke Katagiri, Yui Furuya, Hiroshi Danjo, Tsuneo Imamoto, Kentaro Yamaguchi
ORGANIC LETTERS 8 ( 8 ) 6103 - 6106 2006.11
Joint Work
Publisher：AMER CHEMICAL SOC
Bis(phosphine)boronium salts 3a-c were designed and prepared as key building blocks for the synthesis of highly congested diphosphinobenzenes. The preparation of sterically hindered ortho-phenylene-bridged diphosphines 1a-c was achieved by the reaction of the bis(phosphine)boronium salts 3a-c with difluorobenzenechromium complex 2 and subsequent removal of the BH2 group. The steric nature of diphosphine 1a was revealed in single-crystal X-ray analysis of its Rh complex.
DOI： 10.1021/ol062717i
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Combinatorial approach to heterogeneous asymmetric aquacatalysis with amphiphilic polymer-supported chiral phosphine-palladium complexes Reviewed
Yukinari Kobayashi, Daiki Tanaka, Hiroshi Danjo, Yasuhiro Uozumi
ADVANCED SYNTHESIS & CATALYSIS 348 ( 348 ) 1561 - 1566 2006.6
Joint Work
Publisher：WILEY-V C H VERLAG GMBH
A library of amphiphlic polystyrene-poly(ethylene glycol) (PS-PEG) resin-supported chiral phosphine ligands was prepared by the split method using porous miniature reactors. A polymeric (R)-2-(diphenylphosphino)binaphthyl (MOP) ligand anchored onto the PS-PEG resin by an (S)-alanine tether unit was identified through the library-based screening to be an effective chiral ligand for the asymmetric palladium-catalyzed pi-allylic substitution under heterogeneous aqueous conditions.
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Assembly state of catalytic modules as chiral switches in asymmetric strecker amino acid synthesis Reviewed
Nobuki Kato, Tsuyoshi Mita, Motomu Kanai, Bruno Therrien, Masaki Kawano, Kentaro Yamaguchi, Hiroshi Danjo, Yoshihisa Sei, Akihiro Sato, Sanae Furusho, Masakatsu Shibasaki
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY 128 ( 128 ) 6768 - 6769 2006.5
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P-chiral o-phosphinophenol as a P/O hybrid ligand: Preparation and use in Cu-catalyzed asymmetric conjugate addition of diethylzinc to acyclic enones Invited Reviewed
Y Takahashi, Y Yamamoto, K Katagiri, H Danjo, K Yamaguchi, T Imamoto
JOURNAL OF ORGANIC CHEMISTRY 70 ( 70 ) 9009 - 9012 2005.9
Joint Work
Publisher：AMER CHEMICAL SOC
(S)-2-(tert-Butylmethylphosphino)phenol and its methyl ether were synthesized from tert-butyldichlorophosphine via optically active phosphine-boranes as the intermediates. The former compound was used as a P/O hybrid ligand in the Cu-catalyzed asymmetric conjugate addition of diethylzinc to acyclic enones to achieve high enantioselectivity of up to 96%.
DOI： 10.1021/jo051034y
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Nucleophilic aromatic substitution reactions of fluorobenzenechromium complexes with P-chiral secondary phosphine-boranes: synthesis of optically pure P-chiral (dialkyl)arylphosphine-boranes Reviewed
K Katagiri, H Danjo, K Yamaguchi, T Imamoto
TETRAHEDRON 61 ( 61 ) 4701 - 4707 2005.3
Joint Work
Publisher：PERGAMON-ELSEVIER SCIENCE LTD
Optically pure P-chiral (dialkyl)arylphosphine-boranes having high structural diversity were prepared by two- or three-component coupling of fluorobenzenechromium complexes, P-chiral secondary phosphine-boranes, and other nucleophiles. The stereochernical integrity at the P-stereogenic center was completely retained during the SNAr process when the reaction was carried out in THF at low temperature. (c) 2005 Elsevier Ltd. All rights reserved.
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Dihydroboronium derivatives of (S,S)-1,2-bis(t-butylmethylphosphino)ethane as convenient chiral ligand precursors Reviewed
T Miyazaki, M Sugawara, H Danjo, T Imamoto
TETRAHEDRON LETTERS 45 ( 45 ) 9341 - 9344 2004.11
Joint Work
Publisher：PERGAMON-ELSEVIER SCIENCE LTD
Dihydroboroniurn derivatives of (S,S)-1,2-bis(t-butylmethylphosphino)ethane (t-Bu-BisP*) were prepared and used as chiral diphosphine ligand precursors in Rh-catalyzed asymmetric hydrogenation of methyl (Z)-acetamidocinnamate to afford the hydrogenation product in up to 94% enantioselectivity. (C) 2004 Elsevier Ltd. All rights reserved.
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Cooperative dual catalysis: Application to the highly enantioselective conjugate cyanation of unsaturated imides Reviewed
GM Sammis, H Danjo, EN Jacobsen
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY 126 ( 126 ) 9928 - 9929 2004.7
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P-stereogenic P/N hybrid ligands: a remarkable switch in enantioselectivity in palladium-catalyzed asymmetric allylation Reviewed
H Danjo, M Higuchi, M Yada, T Imamoto
TETRAHEDRON LETTERS 45 ( 45 ) 603 - 606 2003.10
Joint Work
Authorship：Lead author Publisher：PERGAMON-ELSEVIER SCIENCE LTD
Optically active P-stereogenic phosphine/oxazoline bidentate ligands (1) were prepared and applied to palladium-catalyzed allylic substitution of 1,3-diphenyl-1-acetoxy-2-propene with dimethyl malonate. The absolute configuration of the allylation product was remarkably switched by changing a palladium/ligand ratio between 1/1 and 1/2. (C) 2003 Elsevier Ltd. All rights reserved.
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P-Chirogenic phosphonium salts: preparation and use in Rh-catalyzed asymmetric hydrogenation of enamides
H Danjo, W Sasaki, T Miyazaki, T Imamoto
TETRAHEDRON LETTERS 44 ( 44 ) 3467 - 3469 2003.3
Joint Work
Authorship：Lead author Publisher：PERGAMON-ELSEVIER SCIENCE LTD
P-Chirogenic trialkylphosphonium salts were prepared from the corresponding free phosphines by treatment with a strong acid (HBF4 or HOPf). No racemization of the phosphonium salts occurred in methanol or water even at considerably high temperature. The salts were conveniently used in rhodium-catalyzed asymmetric hydrogenation of enamides. (C) 2003 Elsevier Science Ltd. All rights reserved.
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Formation of indole nucleus via intramolecular cyclization of aminophenylpropenyltriphenylphosphonium salts with one-carbon degradation Reviewed
S Taira, H Danjo, T Imamoto
TETRAHEDRON LETTERS 43 ( 43 ) 8893 - 8896 2002.10
Joint Work
Publisher：PERGAMON-ELSEVIER SCIENCE LTD
Treatment of 3-(2-aminoplienyl)-2-propenyltriphenylphosphonium bromide with acid anhydride and tertiary amine affords 1,3-diacylindoles in yields ranging from 22 to 64%. A plausible mechanism of this new cyclization reaction is described. (C) 2002 Published by Elsevier Science Ltd.
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Preparation of an optically active bis(diethylphosphino)biphenyl ligand designed for highly reactive catalytic processes Reviewed
T Shibata, H Tsuruta, H Danjo, T Imamoto
JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL 196 ( 196 ) 117 - 124 2002.7
Joint Work
Publisher：ELSEVIER SCIENCE BV
New optically active diphosphine ligands, (S)-2,2'-bis(diphenylphosphino)-3,3',4,4',5,5',6,6'-octamethylbiphenyl (2a) and (S)-2,2'-bis(diethylphosphino)-3,3',4,4',5,5',6,6'-octamethylbiphenyl (2c) were prepared via optical resolution of the corresponding phosphine oxides. The Rh complex of 2c proved efficient in the catalytic asymmetric hydrogenation of a dehydroamino acid derivative even at -50degreesC and gave 88% e.e. of hydrogenation product quantitatively. (C) 2002 Elsevier Science B.V. All rights reserved.
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A facile synthesis of 2-substituted indoles from (2-aminobenzyl)triphenylphosphonium salts Reviewed
S Taira, H Danjo, T Imamoto
TETRAHEDRON LETTERS 43 ( 43 ) 2885 - 2888 2002.3
Joint Work
Publisher：PERGAMON-ELSEVIER SCIENCE LTD
A variety of 2-substituted 1-acylindoles were obtained in yields ranging from 40 to 94% by intramolecular Wittig reaction employing (2-aminobenzyl)triphenylphosphonium derivatives and acid anhydride in the presence of triethylamine. The reaction of (2-aminobenzyl)phosphonium derivatives with various acyl chlorides in 2.6-lutidine also proceeded to give the corresponding indoles in 28-67% yields. (C) 2002 Elsevier Science Ltd. All rights reserved.
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P-chirogenic phosphine/sulfide hybrid ligands Reviewed
H Sugama, H Saito, H Danjo, T Imamoto
SYNTHESIS-STUTTGART ( 15 ) 2348 - 2353 2001.7
Joint Work
Publisher：GEORG THIEME VERLAG KG
P-Chirogenic phosphine/sulfide hybrid ligands I were prepared by the use of optically active phosphine-boranes as the intermediates. The palladium complexes of the ligands exhibited high catalytic activity and enantioselectivity in allylic alkylation of 1-acetoxy-1,3-diphenylprop-2-ene with malonate esters.
DOI： 10.1055/s-2001-18433