1994 Fiscal Year Annual Research Report

高反応性ビラジカルおよびカチオンラジカルに関する研究

Research Project

Project/Area Number	06044014
Research Institution	Tohoku University
Principal Investigator	宮仕勉東北大学, 理学部, 教授 (20004442)
Co-Investigator(Kenkyū-buntansha)	MCBRIDE J.M. エール大学, 教授 MARIANO P.S. メリーランド大, 教授 HILINSKI E.F フロリダ州立大, 助教授 DINNOCENZO J ロチェスター大, 助教授 GOODMAN J.L. ロチェスター大, 助教授 WAGNER P.J. ミシガン州立大, 教授 BERSON J.A. エール大学, 教授秋山公男東北大, 反応研(H6. 10. 16付), 助教授 (10167851) 高橋康丈東北大学, 理学部, 助手 (70197185) 鈴木孝紀北海道大学, 理学部(H7. 1. 1. 付), 助教授 (70202132) 池田浩東北大学, 理学部, 助手 (30211717)
Keywords	ビラジカル / カチオンラジカル / 逆電子移動 / 光化学 / 光誘起電子移動 / 反応機構 / 閃光光分解 / 光音響法
Research Abstract	平成6年度の派遣研究は研究代表者・宮仕と研究分担者・池田によって行われた宮仕は先ずアメリカ側代表者Berson教授と計画全般に対する研究打ち合わせ及びその方向付けを行ない,またMcBride教授,Hilinski助教授らと具体的な研究打ち合わせを行なった.さらに宮仕は池田と共にRochester大学に赴き,光音響測熱法を適用して光増感電子移動Cope転位系のエネルギー曲面を明かにした. 招聘研究としてはBerson教授,Wagner教授,Goodman助教授及びDinnocenzo助教授が来日し,各々共同研究を行なった.合同討議・情報交換に関してはBerson教授とWagner教授の場合ビラジカルについて,Goodman助教授とDinnocenzo助教授の場合カチオンラジカルについての話題が主となり,何れの場合もその領域だけでは解決不能と思われる難問題があった.それらを解決するには 1)ビラジカルの化学とカチオンラジカルの化学の整合性の確立 2)各々の領域の研究者による活発な情報交換と共同研究の2点が改めて確認され,来年度に向けて新たに具体的な共同実験計画が練られた. これらの研究を通し,学術上の問題点として特に注目されたのが,反応生成物を決定する因子,とりわけビラジカルのモーメント効果の有無である.これは新しい概念で,未だ決定的な証拠が少ないこと,カチオンラジカルの場合発現するか否か?が大きな問題となった.即ち一重項ビラジカル,二重項カチオンラジカル,三重項ビラジカルの三種の多重度を持つラジカル種における動力学的反応支配因子に違いがあるか否か?という問題である.この問題を解決するのが本研究の今後の課題の一つとして挙げられた. なお,平成7年度科学研究費計画調書提出後に派遣研究分担者の変更があり,記載事項が一部異なることを留意されたい.

Research Products

(17 results)

All Other

All Publications (17 results)

[Publications] Takanori Suzuki: "An absolute asymmetric synthesis of the [2+2] cycloadduct via single crystal-to-single crystal transformation by charge-transfer excitation of solid-state molecular complexes composed of arylolefins and bis[1,2,5]thiadiazolotetracyano-quinodimethane." J.Am.Chem.Soc.116. 2793-2803 (1994)
[Publications] Hiroshi Ikeda: "Striking contrast between photoinduced and non-photoinduced electron-transfer reactions of 1,4-diphyenyl-2,3-diazabicyclo[2.2.2]oct-2-ene." J.Chem.Soc.,Chem.Commun.297-298 (1994)
[Publications] Yasutake Takahashi: "Cycloreversion of arene endoperoxides induced by electron transfer." J.Chem.Soc.,Chem.Commun.13-14 (1994)
[Publications] Yasutake Takahashi: "Triplet-state electron-transfer reactions of phyenylcyclopropane with quinones." J.Chme.Soc.,Chem.Commun.1127-1128 (1994)
[Publications] Yasutake Takahashi: "Electron-transfer induced intramolecular [2+2] cycloaddition of 2,6-diarylhepta-1,6-dienes." Tetrahedron Lett.35. 3953-3956 (1994)
[Publications] Yasutake Takahashi: "Electron transfer induced isomerization of cis,trans- and trans,trans-1,4-diphenyl-1,3-butadiene." Tetrahedron Lett.35. 5681-5684 (1994)
[Publications] Takanori Suzuki: "2-(Thiopyran-4'-ylidene)-1,3-dithioles fused with thiophene units:intramolecular S・・・S interaction affecting the redox properties and molecular geometries." J.Chem.Soc.,Chem.Commun.13-14 (1994)
[Publications] Akio Katsuki: "Spin-orbit coupling electron epin polirization observed in photosensitized electron transfer reactions between dyes and p-quinones." J.Am.Chem.Soc.116. 12065-12066 (1994)
[Publications] Kimiko Akiyama: "Spin polarization conservation during intramolecular triplet-triplet energy transfer studied by time-resolved EPR spectroscopy." J.Am.Chem.Soc.116. 5324-5327 (1994)
[Publications] Tania Elaine Wessel: "Stabilization of a putive cycclohexane-1,4-dil intermediate slicits an antrafacial Cope rearrangement via a stepwise mechansim.Phyrolysis of (R,E)-5-methyl-1,2,6-octatriene to 4-methyl-3-methylene-1,5-heheptadiene." J.Am.Chem.Soc.116. 495-565 (1994)
[Publications] Matthew H.J.Cordes: "Stereochemistry of a cyclopropanone by crystal structure analysis.The exo-configuration of the Diels-Alder adducts of cyclopropenone and 1,3-diphenylisobenzofuran appears to be stabilized relative to the endo by an attractive ether-carbonyl interaction." J.Am.Chem.Soc.116. 11161-11162 (1994)
[Publications] P.J.Wagner: "The regioselectivity of internal hydrogene abstraction by triplet o-tert-amylbenzophenone." J.Am.Chem.Soc.116. 589-596 (1994)
[Publications] Kung-Lung Cheng: "Biradical rearrangements during intramolecular cycloaddition of doble bonds to triplet benzenes." J.Am.Chem.Soc.116. 7945-7946 (1994)
[Publications] P.J.Wagner: "Photoinduced radical cleavage of acylphenyl halides:Different mechansims for C-I and C-Br Bonds." J.Am.Chem.Soc.116. 10284-10285 (1994)
[Publications] P.J.Wagner: "Chiral auxiliaries promote both diasteroselective cycloadditions and kinetic resolutions of products in the ortho photocycloaddition of double bondes to benzene rings." J.Am.Chem.Soc.116. 10827-10828 (1994)
[Publications] Xiaoming Zhang: "Dynamics of a-CH deprotonation and a-desilylation reactions of tertially aminecation radicals" J.Am.Chem.Soc.116. 4211-4220 (1994)
[Publications] Xiadong Lin: "A cephalotaxine synthesis founded on a mechanistically interesting,quasi-biomimetic strategy." J.Am.Chem.Soc.116. 9791-9792 (1994)

1994 Fiscal Year Annual Research Report

高反応性ビラジカルおよびカチオンラジカルに関する研究

Principal Investigator

宮仕 勉 東北大学, 理学部, 教授 (20004442)

Research Products

[Publications] Hiroshi Ikeda: "Striking contrast between photoinduced and non-photoinduced electron-transfer reactions of 1,4-diphyenyl-2,3-diazabicyclo[2.2.2]oct-2-ene." J.Chem.Soc.,Chem.Commun.297-298 (1994)

[Publications] Yasutake Takahashi: "Cycloreversion of arene endoperoxides induced by electron transfer." J.Chem.Soc.,Chem.Commun.13-14 (1994)

[Publications] Yasutake Takahashi: "Triplet-state electron-transfer reactions of phyenylcyclopropane with quinones." J.Chme.Soc.,Chem.Commun.1127-1128 (1994)

[Publications] Yasutake Takahashi: "Electron-transfer induced intramolecular [2+2] cycloaddition of 2,6-diarylhepta-1,6-dienes." Tetrahedron Lett.35. 3953-3956 (1994)

[Publications] Yasutake Takahashi: "Electron transfer induced isomerization of cis,trans- and trans,trans-1,4-diphenyl-1,3-butadiene." Tetrahedron Lett.35. 5681-5684 (1994)

[Publications] Takanori Suzuki: "2-(Thiopyran-4'-ylidene)-1,3-dithioles fused with thiophene units:intramolecular S・・・S interaction affecting the redox properties and molecular geometries." J.Chem.Soc.,Chem.Commun.13-14 (1994)

[Publications] Akio Katsuki: "Spin-orbit coupling electron epin polirization observed in photosensitized electron transfer reactions between dyes and p-quinones." J.Am.Chem.Soc.116. 12065-12066 (1994)

[Publications] Kimiko Akiyama: "Spin polarization conservation during intramolecular triplet-triplet energy transfer studied by time-resolved EPR spectroscopy." J.Am.Chem.Soc.116. 5324-5327 (1994)

[Publications] Tania Elaine Wessel: "Stabilization of a putive cycclohexane-1,4-dil intermediate slicits an antrafacial Cope rearrangement via a stepwise mechansim.Phyrolysis of (R,E)-5-methyl-1,2,6-octatriene to 4-methyl-3-methylene-1,5-heheptadiene." J.Am.Chem.Soc.116. 495-565 (1994)

[Publications] P.J.Wagner: "The regioselectivity of internal hydrogene abstraction by triplet o-tert-amylbenzophenone." J.Am.Chem.Soc.116. 589-596 (1994)

[Publications] Kung-Lung Cheng: "Biradical rearrangements during intramolecular cycloaddition of doble bonds to triplet benzenes." J.Am.Chem.Soc.116. 7945-7946 (1994)

[Publications] P.J.Wagner: "Photoinduced radical cleavage of acylphenyl halides:Different mechansims for C-I and C-Br Bonds." J.Am.Chem.Soc.116. 10284-10285 (1994)

[Publications] P.J.Wagner: "Chiral auxiliaries promote both diasteroselective cycloadditions and kinetic resolutions of products in the ortho photocycloaddition of double bondes to benzene rings." J.Am.Chem.Soc.116. 10827-10828 (1994)

[Publications] Xiaoming Zhang: "Dynamics of a-CH deprotonation and a-desilylation reactions of tertially aminecation radicals" J.Am.Chem.Soc.116. 4211-4220 (1994)

[Publications] Xiadong Lin: "A cephalotaxine synthesis founded on a mechanistically interesting,quasi-biomimetic strategy." J.Am.Chem.Soc.116. 9791-9792 (1994)

宮仕勉東北大学, 理学部, 教授 (20004442)