Misc - OSUGA Hideji

らせん分子ヘリセンの合成と超分子構造・分子認識

大須賀秀次・田中和彦

第78回有機合成シンポジウム講演要旨集     79-82   2000.09

両末端を架橋したチアヘテロヘリセンの合成と機能・構造

大須賀秀次・北原芳徳・田中和彦

第30回複素環化学討論会講演要旨集     110-113   1999.11

Synthesis, enzymic resolution and enantiomeric enhancement of bis(hydroxymethyl)[7]thiaheterohelicenes

K Tanaka, H Osuga, H Suzuki, Y Shogase, Y Kitahara

JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 1 ( ROYAL SOC CHEMISTRY )  ( 5 ) 935 - 940   1998.03

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Racemic bis(hydroxymethyl)[7]thiaheterohelicene 9 has been prepared in eight steps (33% overall yield) from 2-(hydroxymethyl)benzo[1,2-b:4,3-b']dithiophene 1. Lipase (Pseudomonas cepacia)-catalyzed transesterification of diol 9 by vinyl acetate in dichloromethane produces optically stable (P)-bis(hydroxymethyl)[7]thiaheterohelicene [(P)-9] with 98% ee along with the corresponding monoacetate [(M)-10] and the diacetate [(M)-11]. Hydrolysis of acetates (M)-10 and (M)-11 by aq, NaOH gives (M)-9 in 77% and 94% ee, respectively, In contrast, the enzymic resolution of diol 9 with Candida antarctica afforded diol (IM)-9 in 92% ee, Column chromatography of optically enriched helicenediol 9 on silica gel shows an enantiomeric enhancement. A possible cause of the phenomenon is discussed.

A novel route to disubstituted [7]thiaheterohelicene via biaryl- and carbonyl-coupling reactions

K Tanaka, H Suzuki, H Osuga

TETRAHEDRON LETTERS ( PERGAMON-ELSEVIER SCIENCE LTD )  38 ( 3 ) 457 - 460   1997.01

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A new non-photochemical synthesis of disubstituted heterohelicene is described. The directed metalation at the I-position of 2-(4,4-dimethyloxazolin-2-yl)-7-methylbenzo[1,2-b:4,3-b']dithiophene was accomplished by the use of BuLi in ether to give the organolithium species which, upon treatment with iodine and chlorotributyltin, gave 2-(4,4-dimethyloxazolin-2-yl)-1-iodo-7-methylbenzo-[1,2-b:4,3-b']-dithiophene and 2-(4,4-dimethyloxazolin-2-yl)-7-methyl-1-tributylstannylbenzo-[1,2-b:4,3-b']dithiophene in high yields. Palladium-catalyzed cross-coupling between them, followed by the intramolecular McMurry coupling reaction, gave 2,13-dimethyl[7]thiaheterohelicene in good yield. Copyright (C) 1996 Elsevier Science

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Synthesis and crystal structure of functionalized chiral [7]thiaheterohelicenes

K Tanaka, H Osuga, K Koyama, H Suzuki, K Imai, Y Yoshida

ENANTIOMER ( GORDON BREACH SCI PUBL LTD )  2 ( 3-4 ) 193 - 201   1997

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The diastereocontrolled photocyclization of 1,2-diarylethylene (3) derived from (1R,2S,3R,4S)-3-amino-2-hydroxybornane as a chiral auxiliary has been employed as the key step in the synthesis of functionalized chiral helicenes containing (ethylthio)carbonyl, hydroxymethyl, chloromethyl, formyl and (triphenylphosyhonio)methyl groups at the 2-position of [1]benzothieno[5,4-b]naphtho[1'2':4,5]thieno[3,2-e][1]benzothiophene. These chiral helicenes show very high rotational values, [alpha](D) 1450-2900, and the absolute configuration of [7](heterohelicene) carboxamide possessing a positive rotational value has been determined as P, a right-handed helicity by X-ray crystallography. In the crystal lattice, the hydrogen bond between OH of the 3-amino-2-hydroxybornane moiety and the carbonyl oxygen located on the adjacent molecule forms a helical network. The interplanar angle between the terminal rings of the helicene is 47.3 degrees and the shortest nonbonded C-C distance is 3.05 Angstrom.

Synthesis, structure and properties of [7]heterohelicenes possessing phenolic hydroxy functions

K Tanaka, T Kume, T Takimoto, Y Kitahara, H Suzuki, H Osuga, Y Kawai

CHEMISTRY LETTERS ( CHEMICAL SOC JAPAN )  ( 6 ) 501 - 502   1997

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Photocyclization of 2,7-bis[3-(t-butyldimethylsilyloxy)-phenylvinylene]benzo[1,2-b:4,3-b']dithiophene affords three regioisomers of the bis(silyloxy)[7]thiaheterohelicenes together with the unexpected 4-phenyl-substituted [7]thiaheterohelicene. Cleavage of the silyl ethers gave the helical quinone, which includes ethanol as guest molecules to form a 1:1 inclusion complex.

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COMPLEXATION WITH HELICAL MOLECULES - HELICAL CRYSTAL-STRUCTURE OF BIS(HYDROXYMETHYL)[7]THIAHETEROHELICENE ETHANOL CLATHRATE

K TANAKA, Y SHOGASE, H OSUGA, H SUZUKI, W NAKANISHI, K NAKAMURA, Y KAWAI

JOURNAL OF THE CHEMICAL SOCIETY-CHEMICAL COMMUNICATIONS ( ROYAL SOC CHEMISTRY )  ( 18 ) 1873 - 1874   1995.09

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Bis(hydroxymethyl)[7]thiaheterohelicene affords a crystalline host-guest inclusion complex with ethanol having a 1:1 host-guest ratio self-assembled through a helical network of hydrogen bonds.

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COMPLEXATION WITH HELICAL MOLECULES - HELICAL CRYSTAL-STRUCTURE OF BIS(HYDROXYMETHYL)[7]THIAHETEROHELICENE ETHANOL CLATHRATE

K TANAKA, Y SHOGASE, H OSUGA, H SUZUKI, W NAKANISHI, K NAKAMURA, Y KAWAI

JOURNAL OF THE CHEMICAL SOCIETY-CHEMICAL COMMUNICATIONS ( ROYAL SOC CHEMISTRY )  ( 18 ) 1873 - 1874   1995.09

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Bis(hydroxymethyl)[7]thiaheterohelicene affords a crystalline host-guest inclusion complex with ethanol having a 1:1 host-guest ratio self-assembled through a helical network of hydrogen bonds.

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CARBOHELICENES, HETEROHELICENES AND RELATED SYSTEMS - SOME ASPECTS OF SYNTHESIS AND REACTIONS

H OSUGA, H SUZUKI

JOURNAL OF SYNTHETIC ORGANIC CHEMISTRY JAPAN ( SOC SYNTHETIC ORGANIC CHEM JPN )  52 ( 12 ) 1020 - 1031   1994.12

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Helicenes are a class of helically condensed polycyclic aromatic compounds, which are characterized by the rigid helicity and high optical stability, Since the first synthesis and optical resolution of [6] helicene by Newman and Lednicer in 1955, the chemistry of helicenes has attracted continuing attention because of their unique structural features and high rotational values. The purpose of this article is to make a survey of the development and present situation of helicene chemistry, emphasis being placed on the synthetic aspects, optical resolution and reactions of helicenes and heterohelicenes. Also included are some of helicene analogues such as double helicenes, bihelicenes, propelicenes and circulenes.

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STEREOCONTROLLED CYCLOPROPANATION OF ALPHA,BETA-UNSATURATED CARBOXAMIDES DERIVED FROM BICYCLIC AMINO-ALCOHOLS

K TANAKA, H UNO, H OSUGA, H SUZUKI

TETRAHEDRON-ASYMMETRY ( PERGAMON-ELSEVIER SCIENCE LTD )  5 ( 7 ) 1175 - 1178   1994.07

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The asymmetric cyclopropanation of the exo-N-[(1R,2S,3R,4S)-2-hydroxy-1,7,7-trimethylbicyclo[2.2.1]hept-3-yl]-3-phenyl-2-propenamide and the endo-( 1R,2R,3S,4S)-isomer with Et(2)Zn/CH2I2 proceeded with predictable absolute stereochemistry. The exo-amide gave the (1R,2R)-cyclopropane derivative selectively (de less than or equal to 80%), while the endo-amide gave the (1S,2S)-isomer (de less than or equal to 58%). Complete reversal of the stereoselectivity (98% de) was observed when O-triisopropyl derivatives of the amides were used in the cyclopropanation.

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STEREOCONTROLLED CYCLOPROPANATION OF ALPHA,BETA-UNSATURATED CARBOXAMIDES DERIVED FROM BICYCLIC AMINO-ALCOHOLS

K TANAKA, H UNO, H OSUGA, H SUZUKI

TETRAHEDRON-ASYMMETRY ( PERGAMON-ELSEVIER SCIENCE LTD )  5 ( 7 ) 1175 - 1178   1994.07

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The asymmetric cyclopropanation of the exo-N-[(1R,2S,3R,4S)-2-hydroxy-1,7,7-trimethylbicyclo[2.2.1]hept-3-yl]-3-phenyl-2-propenamide and the endo-( 1R,2R,3S,4S)-isomer with Et(2)Zn/CH2I2 proceeded with predictable absolute stereochemistry. The exo-amide gave the (1R,2R)-cyclopropane derivative selectively (de less than or equal to 80%), while the endo-amide gave the (1S,2S)-isomer (de less than or equal to 58%). Complete reversal of the stereoselectivity (98% de) was observed when O-triisopropyl derivatives of the amides were used in the cyclopropanation.

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Carbohelicenes, Heterohelicences and Related Systems-Some Aspects of Synthesis and Reactions

Hideji Osuga, Hitomi Suzuki

Yuki Gosei Kagaku Kyokaishi/Journal of Synthetic Organic Chemistry   52 ( 12 ) 1020 - 1031   1994

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Helicenes are a class of helically condensed polycyclic aromatic compounds, which are characterized by the rigid helicity and high optical stability, Since the first synthesis and optical resolution of [ 6 ] helicene by Newman and Lednicer in 1955, the chemistry of helicenes has attracted continuing attention because of their unique structural features and high rotational values. The purpose of this article is to make a survey of the development and present situation of helicene chemistry, emphasis being placed on the synthetic aspects, optical resolution and reactions of helicenes and heterohelicenes. Also included are some of helicene analogues such as double helicenes, bihelicenes, propelicenes and circulenes. © 1994, The Society of Synthetic Organic Chemistry, Japan. All rights reserved.

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