Studies on catalytic enantioselective protonation

• Project/Area Number: 08640699
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Organic chemistry
• Research Institution: Niigata College of Pharmacy
• Principal Investigator: NAKAMURA Yutaka (1997-1998) Niigata College of Pharmacy, Faculty of Pharmaceutical Sciences, Research Associate, 薬学部, 助手 (20267652); 武内 征司 (1996) 新潟薬科大学, 薬学部, 助教授 (00131011)
• Co-Investigator(Kenkyū-buntansha): 中村 豊 新潟薬科大学, 薬学部, 助手 (20267652)
• Project Period (FY): 1996 – 1998
• Project Status: Completed (Fiscal Year 1998)
• Budget Amount: ¥2,300,000 (Direct Cost: ¥2,300,000); Fiscal Year 1998: ¥300,000 (Direct Cost: ¥300,000); Fiscal Year 1997: ¥200,000 (Direct Cost: ¥200,000); Fiscal Year 1996: ¥1,800,000 (Direct Cost: ¥1,800,000)
• Keywords: samarium enolate / enantioselective protonation / catalytic reaction / ヨウ化サマリウム / C_2-対称キラルジオール

Research Abstract

(1) Enantioselectivities near maximum values were obtained in the catalytic enantioselective protonation of samarium enolate by a rapid addition of a fluorous achiral alcohol (Rfh_33C-OH) to the reaction mixture : for a nonfluorous chiral diol (DHPEX) in Rfh_3C-OH/THF solid-liquid biphase system and for a fluorous chiral alcohol in THF/FC-72 liquid-liquid biphase system.
(2) High enantioselectivity (up to 94% ee) has been achieved in the enantioselective protonation of samarium enolates generated by SmI_2-mediated reductive elimination of alpha-hetero-substituted ketones using C_2-symmetric chiral diol as a proton source.

Research Products

• [Publications] Seiji Takeuchi: "Catalytic Enantioselective Protonation of a Samarium Enolate with Fluorous Chiral and Achiral Proton Sources in Fluorous Biphasic Systems" Tetrahedron Letters. 39. 8691-8694 (1998)
  • Description: 「研究成果報告書概要(和文)」より
• [Publications] Yutaka Nakamura: "Enantioselective Protonation of Samarium Enolates Derived from α-heterosubstituted Ketones and Lactones by SmI_2-Mediated Reduction" Tetrahedron. 55. 4595-4620 (1999)
  • Description: 「研究成果報告書概要(和文)」より
• [Publications] Seiji Takeuchi: "Catalytic Enantioselective Protonation of a Samarium Enolate with Fluorous Chiral and Achiral Proton Sources in Fluorous Biphasic Systems" Tetrahedron Lett. 39(47). 8691-8694 (1998)
  • Description: 「研究成果報告書概要(欧文)」より
• [Publications] Yutaka Nakamura: "Enantioselective Protonation of Samarium Enolates Derived from alpha-heterosubstituted Ketones and Lactones by SmI_2-Mediated Reduction" Tetrahedron. 55(15). 4595-4620 (1999)
  • Description: 「研究成果報告書概要(欧文)」より
• [Publications] Seiji Takeuchi et al: "Catalytic Enantioselective Protonation of a Samarium Enolate with Fluorous Chiral and Achiral Proton Sources in Fluorous Biphasic Systems" Tetrahedron Letters. 39(47). 8691-8694 (1998)
• [Publications] 中村豊: "Catalytic Enantioselective Protonation of Samarium Enolates by A C_2-Symmetric Chiral Diol" Tetrahedron Letters. 37・16. 2805-2808 (1996)