Preparation and Properties of New Organic Magentic Material

新型有机磁性材料的制备及性能

• 批准号: 05640656
• 负责人: TAMURA Rui
• 金额: $ 1.28万
• 依托单位: Ehime University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1993
• 资助国家: 日本
• 起止时间: 1993 至 1994
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-05640656/
• 关键词: Nitroxide Radical; Radical Anion; Spontaneous Resolution; Conglomerate; Nitro Compound; Samarium Iodide; Optically Active Crystal; Helical Crystal Structure; ホモアリルニトロ化合物

A new methodology for the synthesis of alpha-asymmetric bicyclic nitroxides is described. Reduction of certain homoallylic nitroenone with 3.0 equiv of Sml_2 in THF or THF-Et_2O at-50ﾟC gave a stable nitroxide radical-enolate intermediate, a kind of radical-anion species.The subsequent addition of electrophiles such as acyl chlorides at-50ﾟC resulted in the O-acylation of the enolate moiety to form the corresponding neutral nitroxide radical. The reduction process was quite sensitive to the substrate structure, amount of Sml_2, solvent composition and reaction temperature. The optimum reaction conditions for this two-step reaction were determined. Analytically pure stable nitroxide radicals were isolated in good to fair yields when benzoyl chlorides substituted by electron-withdrawing groups were used as the electrophile for O-acylation. Although the use of organosilyl chlorides and alkylating reagents as the electrophile seemd to provide the corresponding radical products in the reaction mixture, pure redical products were not obtained. The mechanism of formation of the nitroxide radical-enolate intermediate was investigated by ESR spectroscopy and the product analysis.

介绍了一种合成α-不对称双环氮氧自由基的新方法。在THF或THF-Et_2 O中，3.0equivSml_2在-50 ° C还原高烯丙基氮烯酮，得到稳定的氮氧自由基-烯醇化物中间体，然后在-50 ° C加入亲电试剂如酰氯，烯醇化物部分发生O-酰化反应，生成相应的中性氮氧自由基。还原过程对底物结构、Sml_2用量、溶剂组成和反应温度十分敏感。确定了该两步反应的最佳反应条件。分析纯的稳定的氮氧自由基被隔离在良好的公平产率时，取代吸电子基团的苯甲酰氯被用作O-酰化的亲电试剂。虽然使用有机硅氯化物和烷基化试剂作为亲电试剂可以在反应混合物中提供相应的自由基产物，但不能获得纯的自由基产物。通过ESR波谱和产物分析研究了氮氧自由基-烯醇化物中间体的形成机理。

项目成果

R.Tamura,M.Kohno,S.Utsunomiya,K.Yamawaki,et al.: "Synthesis of PGB_1 Analogues by Radical Chain Substitution Reaction" The Journal of Organic Chemistry. 58. 3953-3959 (1993)

R.Tamura、M.Kohno、S.Utsunomiya、K.Yamawaki 等人：“通过自由基链取代反应合成 PGB_1 类似物”有机化学杂志。

R.Tamura,et al.: "Preparation and Properties of Chiral Nitroxide Radicals with Helical Crystal Structure" Molecular Crystals and Liquid Crystals. (印刷中). (1995)

R. Tamura 等人：“具有螺旋晶体结构的手性硝基氧自由基的制备和性质”分子晶体和液晶（出版中）。

R.Tamura,S.Susuki,N.Azuma,A.Matsumoto,F.Toda,et al.: "Preparation and Spontaneous Optical Resolution of Nitroxide conglomerate Assuming Spiral Crystal Structure" Angewandte Chemie International Edition English. 33 (印刷中). (1994)

R. Tamura、S. Susuki、N. Azuma、A. Matsumoto、F. Toda 等人：“采用螺旋晶体结构的硝基氧化物砾岩的制备和自发光学拆分”Angewandte Chemie 国际版英文版 33（印刷中）。 (1994)

R.Tamura: "Preparation and properties of chiral nitroxide radicals with helical crystal structure" Molecular Crystals and Liquid Crystals. (in press).

R.Tamura：“具有螺旋晶体结构的手性氮氧自由基的制备和性质”分子晶体和液晶。

R.Tamura: "Preparation of Chiral Nitroxide Radicals and Spontaneous Optical Resolution by Recrystallization" Angewandt Chemie International Edition English. 33. 878-879 (1994)

R.Tamura：“通过重结晶制备手性氮氧自由基和自发光学拆分”Angewandt Chemie 国际版英文版。