Enantioselective trapping of an α-chiral carbanion next to conjugating electron-withdrawing groups

• Project/Area Number: 23659007
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Chemical pharmacy
• Research Institution: Hiroshima University
• Principal Investigator: TAKEDA Kei 広島大学, 大学院・医歯薬保健学研究科, 教授 (30135032)
• Co-Investigator(Kenkyū-buntansha): SASAKI Michiko 広島大学, 大学院・医歯薬保健学研究院, 准教授 (30379888)
• Project Period (FY): 2011 – 2012
• Project Status: Completed (Fiscal Year 2012)
• Budget Amount: ¥3,770,000 (Direct Cost: ¥2,900,000、Indirect Cost: ¥870,000); Fiscal Year 2012: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000); Fiscal Year 2011: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000)
• Keywords: キラルカルバニオン / 不斉合成 / 有機合成 / 合成化学 / アミノ酸 / 有機化学 / 立体化学

Research Abstract

(1) We have demonstrated that a chiral α-nitrile carbanion generated by deprotonation of enantioenriched O-carbamoylcyanohydrin is able to be trapped by a carbon electrophile.
(2) Chirality transfer from an α-silylalcohol to α-carbmoyloxy carbanions was investigated using a Brook rearrangement-mediated SE2’ protonation. Comparison of the extent of the chirality transfer provides a new method for semi-quantitative evaluation of the propensity for racemization of lithiocarbanions next to a conjugative electron -withdrawing group.

Research Products

• [Journal Article] Chirality Transfer in Brook Rearrangement-Mediated SE2' Solvolytic Protonation and Its Use in Estimation of the Propensity for Racemization of the α-Lithiocarbanions of the Substituents (2013)
  • Author(s): Michiko Sasaki, Misato Fujiwara, Yuri Kotomori, Masatoshi Kawahata, Kentaro Yamaguchi, Kei Takeda
  • Journal Title: Tetrahedron Volume: 69 Pages: 5823-5828
  • Peer Reviewed
• [Journal Article] Synthetic Potential of Configurationally Unstable Chiral Carbanions (2013)
  • Author(s): 佐々木道子
  • Journal Title: Journal of Synthetic Organic Chemistry, Japan Volume: 71 Issue: 2 Pages: 136-148
  • DOI: 10.5059/yukigoseikyokaishi.71.136
  • NAID: 10031148205
  • ISSN: 0037-9980, 1883-6526
  • Peer Reviewed
• [Journal Article] Enantioselective Trapping of an α-Chiral Carbanion of Acyclic Nitrile by a Carbon Electrophile (2012)
  • Author(s): Michiko Sasaki, Tomo Takegawa, Hidaka Ikemoto, Masatoshi Kawahata, Kentaro Yamaguchi, Kei Takeda
  • Journal Title: Chem. Commun Volume: 48 Pages: 2897-2899
  • Peer Reviewed
• [Journal Article] Enantioselective Trapping of an a-Chiral Carbanion of Acyclic Nitrile by a Carbon Electrophile (2012)
  • Author(s): Michiko Sasaki
  • Journal Title: Chemical Communications Volume: 48 Issue: 23 Pages: 2897-2899
  • DOI: 10.1039/c2cc00082b
  • Peer Reviewed
• [Journal Article] Synthetic Potential of Configurationally Unstable Chiral Carbanions (2012)
  • Author(s): Michiko Sasaki
  • Journal Title: Synlett Volume: 23 Issue: 15 Pages: 2153-2164
  • DOI: 10.1055/s-0031-1290440
  • NAID: 10031148205
  • Peer Reviewed
• [Journal Article] DISCUSSION ADDENDUM FOR: [3 + 4] Annulation Using a [β-(Trimethylsilyl)acryloyl]silane and the Lithium Enolate of an α,β-Unsaturated Methyl Ketone: (1R,6S,7S)-4-(tert-Butyldimethylsiloxy)-6-(trimethylsilyl)bicyclo[5.4.0]undec-4-en-2-one (2012)
  • Author(s): Kei Takeda
  • Journal Title: Organic Syntheses Volume: 89 Pages: 267-273
  • Peer Reviewed
• [Journal Article] Steric Course of the Electrophilc Substitution of a Lithiocarbanion Generated from (S,E)-1-Phenylbut-2-en-1-yl Diisopropylcarbamate and Solvent Effects (2011)
  • Author(s): Hidaka Ikemoto, Michiko Sasaki, Masatoshi Kawahata, Kentaro Yamaguchi, Kei Takeda
  • Journal Title: Eur. J. Org. Chem Pages: 6553-6557
  • Peer Reviewed
• [Journal Article] Steric Course of the Electrophilc Substitution of a Lithiocarbanion Generated from (S,E)-1-Phenylbut-2-en-1-yl Diisopropylcarbamate and Solvent Effects (2011)
  • Author(s): Hidaka Ikemoto
  • Journal Title: European Journal of Organic Chemistry Volume: 2011 Issue: 32 Pages: 6553-6557
  • DOI: 10.1002/ejoc.201100970
  • Peer Reviewed
• [Presentation] Enantioselective trapping of an α-chiral carbanion of acyclic nitrile by a carbon electrophile (2013)
  • Author(s): Kei Takeda
  • Organizer: 19th International Conference on Organic Synthesis
  • Place of Presentation: Melbourne, Australia
• [Presentation] ウレイド基のキレーションを利用するキラルα-ニトリルカルバニオンの発生と求電子剤との反応 (2013)
  • Author(s): 武田 敬
  • Organizer: 日本薬学会第133年会
  • Place of Presentation: 横浜
• [Presentation] エポキシシラン転位を利用するシリルケテンイミンの発生とその反応 (2013)
  • Author(s): 武田 敬
  • Organizer: 日本薬学会第133年会
  • Place of Presentation: 横浜
• [Presentation] 光学活性α-ヒドロキシアリルシランの異性化反応における不斉転写の機構 (2013)
  • Author(s): 武田 敬
  • Organizer: 日本薬学会第133年会
  • Place of Presentation: 横浜
• [Presentation] キラルリチウムアミドを利用するイミンの不斉還元反応 (2013)
  • Author(s): 武田 敬
  • Organizer: 日本薬学会第133年会
  • Place of Presentation: 横浜
• [Presentation] Evaluation of the configurational stability of carbanions next to conjugating electron-withdrawing groups (2012)
  • Author(s): Kei Takeda
  • Organizer: 19th International Conference on Organic Synthesis
  • Place of Presentation: Melbourne, Australia
• [Presentation] Enantioselective Diels-Alder reactions using aminooxazolidinone type organocatalysts (2012)
  • Author(s): Kei Takeda
  • Organizer: 19th International Conference on Organic Synthesis
  • Place of Presentation: Melbourne, Australia
• [Presentation] 共役性電子求引基およびヘテロ原子置換基に隣接するキラルカルバニオンのラセミ化傾向の比較 (2012)
  • Author(s): 武田 敬
  • Organizer: 第38回反応と合成の進歩シンポジウム
  • Place of Presentation: 東京
• [Presentation] カルバモイル基により立体化学的に安定化されたキラルα-ニトリルカルバニオンの捕捉 (2012)
  • Author(s): 武田 敬
  • Organizer: 第102回有機合成シンポジウム
  • Place of Presentation: 東京
• [Presentation] Mechanistic Study of Stereoselective SE2' Protonation of a-Hydroxy Allyl Silanes (2012)
  • Author(s): Kei Takeda
  • Organizer: 12th International Kyoto Conference on New Aspects of Organic Chemistry (IKCOC-12)
  • Place of Presentation: Kyoto
• [Presentation] Enantioselective Trapping of Chiral a-Nitrile Carbanions (2012)
  • Author(s): Kei Takeda
  • Organizer: 12th International Kyoto Conference on New Aspects of Organic Chemistry (IKCOC-12)
  • Place of Presentation: Kyoto
• [Presentation] β位に電子求引基を有するシクロプロピルアシルシランと求核剤との反応 (2012)
  • Author(s): 藤原美智 ，佐々木道子，武田 敬
  • Organizer: 日本薬学会第132年会
  • Place of Presentation: 札幌市
• [Presentation] キラルα-ニトリルカルバニオンの求電子剤による捕捉 (2) (2012)
  • Author(s): 竹川 友 ，佐々木道子，武田 敬
  • Organizer: 日本薬学会第132年会
  • Place of Presentation: 札幌市
• [Presentation] キラルリチウムアミドによる還元を鍵反応とするアレン類のエナンチオ選択的合成 (2012)
  • Author(s): 近藤泰博，佐々木道子，武田 敬
  • Organizer: 日本薬学会第132年会
  • Place of Presentation: 札幌市
• [Presentation] Enantioselective Synthesis of Allenes via Tandem Enantioselective Reduction/Brook Rearrangement (2011)
  • Author(s): Yasuhiro Kondo, Michiko Sasaki, Kei Takeda
  • Organizer: 10th International Symposium on Organic Reactions
  • Place of Presentation: Yokohama
• [Presentation] 共役性電子求引性基に隣接するキラルカルバニオンの立体化学的安定性の評価 (2) (2011)
  • Author(s): 藤原美智，佐々木道子，池本陽峰，武田 敬
  • Organizer: 第50回日本薬学会・日本病院薬剤師会中国四国支部学術大会
  • Place of Presentation: 高松市
• [Presentation] アリルベンジルリチオカルバニオンに対する求電子置換反応の立体化学ー求電子剤と溶媒の効果ー (2011)
  • Author(s): 池本陽峰，佐々木道子, 武田 敬
  • Organizer: 第100回有機合成シンポジウム
  • Place of Presentation: 東京
• [Presentation] 脱プロトン化によるキラルα- ニトリルカルバニオンの発生と捕捉 (2011)
  • Author(s): 竹川 友，佐々木道子，池本陽峰, 武田 敬
  • Organizer: 第100回有機合成シンポジウム
  • Place of Presentation: 東京
• [Presentation] 光学活性シロキシアレン類の合成と[4 + 2]型環化付加による捕捉 (2011)
  • Author(s): 佐々木道子, 近藤泰博, 武田 敬
  • Organizer: 第37回反応と合成の進歩シンポジウム
  • Place of Presentation: 徳島市
• [Presentation] Chiral Organolithiums Next to a Conjugative Electron-Withdrawing Group: Their Configurational Stability and Enantioselective Trapping by an Electrophile (2011)
  • Author(s): Hidaka Ikemoto, Michiko Sasaki, Misato Fujiwara, Tomo Takegawa, Kei Takeda
  • Organizer: The 242nd National Meeting of the American Chemical Society
  • Place of Presentation: Denver, Colorado, USA.
• [Presentation] Chiral Organolithiums Next to a Conjugative Electron-Withdrawing Group: Their Configurational Stability and Enantioselective Trapping by an Electrophile (2011)
  • Author(s): Hidaka Ikemoto, Michiko Sasaki, Misato Fujiwara, Tomo Takegawa, Kei Takeda
  • Organizer: The 242nd National Meeting of the American Chemical Society, Sci-Mix
  • Place of Presentation: Denver, Colorado, USA.
• [Presentation] Enantioselective Synthesis of Siloxyallenes from Alkynoylsilanes Via Tandem Enantioselective Reduction/Brook Rearrangement and Their Subsequent Trapping by [4 + 2] Cycloaddition (2011)
  • Author(s): Yasuhiro Kondo, Michiko Sasaki, Kei Takeda
  • Organizer: 42nd National Organic Chemistry Symposium
  • Place of Presentation: Princeton, NJ, USA
• [Presentation] Enantioselective Generation of Mesomerically-Stabilized Lithiocarbanions and Evaluation of Their Configurational Stability (2011)
  • Author(s): Michiko Sasaki, Tomo Takegawa, Misato Fujiwara, Hidaka Ikemoto, Kei Takeda
  • Organizer: 42nd National Organic Chemistry Symposium
  • Place of Presentation: Princeton, NJ, USA
• [Presentation] 共役性電子求引基に隣接するキラルカルバニオンの立体化学的安定性の評価法の開発とその求電子剤による捕捉 (2011)
  • Author(s): 池本陽峰，佐々木道子，藤原美智，竹川 友，武田 敬
  • Organizer: 第9回次世代を担う有機化学シンポジウム
  • Place of Presentation: 東京
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