CONTROL OF MOLECULAR CONFORMATION BY CRYSTALLIZATION AND THE APPLICATION TO SUSTAINABLE CHEMISTRY

通过结晶控制分子构象及其在可持续化学中的应用

• 批准号: 17205011
• 负责人: SAKAMOTO Masami
• 金额: $ 32.03万
• 依托单位: Chiba University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 2005
• 资助国家: 日本
• 起止时间: 2005 至 2007
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-17205011/
• 关键词: Organic Crystal; Control of molecular structure; Sustainable Organic Synthesis; Stereoselctive Reaction; Asymmetric Synthesis; Solid-state Reaction; Entropy Control; Photochemical Reaction

Organic crystals provide specific environment where the molecular arrangement and the conformation are strongly influenced by crystal packing. Therefore, the organic crystals were widely utilized to product- and stereo-selective reactions. In this research project, we studied sustainable chemistry in the crystalline environment involving asymmetric synthesis and stereo-selective reactions.(Result 1) Several aromatic amides derived from L-proline, which exist as a mixture of several diastereomers in solution, converged to single diastereomer by crystallization. And the conformational transformation was controlled after the crystals were dissolved in the solvent at low temperature, where the frozen conformation was retained long enough for subsequent asymmetric reaction.(Result 2) Anew methodology using the molecular homochirality in the crystal as a source of homochirality in solution was explored. The chirality can be effectively transferred to optically active products by asymmetric reactions involving a nucleophilic reaction, an intermolecular 4+4 photochemical cycloaddition reaction, a SNAr reaction, a 2+2 photochemical cyclobutane formation with almost quantitative enantiomeric yields.(Result 3) The molecular homochirality generated by crystallization was utilized to kinetic resolution of sec-BuLi and cyclic amines with moderate enantiomeric yields.(Result 4) We found that several axially chiral N-arylpyrimidinones and pyrimidinethiones gave conglomerate crystals, and crystallization at high temperature lead to chiral breaking of symmetry to give optically active materials up to 90% ee without any outside chiral source.

有机晶体提供了特定的环境，其中分子排列和构象受到晶体堆积的强烈影响。因此，有机晶体被广泛用于产物选择性和立体选择性反应。在这个研究项目中，我们研究了结晶环境中的可持续化学，包括不对称合成和立体选择性反应。（结果1）由L-脯氨酸衍生的几种芳香酰胺在溶液中以几种非对映异构体的混合物存在，通过结晶聚合成单一的非对映异构体。低温溶解后，晶体的构象转变受到控制，冻结构象保持足够长的时间以进行后续的不对称反应。（结果2）探索了一种利用晶体中的分子同手性作为溶液中同手性来源的新方法。通过亲核反应、分子间4+4光化学环加成反应、SNAr反应、2+2光化学环丁烷形成等不对称反应，手性可以有效地转化为光学活性产物，对映体产率几乎为定量。（结果3）利用结晶过程中产生的分子同手性对仲丁基锂和环胺进行了动力学拆分，对映体产率适中。（结果4）我们发现几种轴向手性N-芳基嘧啶酮和嘧啶硫酮化合物均能得到聚集晶体，高温结晶导致对称性手性破缺，在没有任何外部手性源的情况下，得到ee值高达90%的光学活性材料。

项目成果

Spontaneous chiral crystallization of achiral materials and absolute asymmetric photochemical transformation using the chiral crystalline environment

• DOI: 10.1016/j.jphotochemrev.2006.11.002
• 发表时间: 2006-12
• 期刊: Journal of Photochemistry and Photobiology C-photochemistry Reviews
• 影响因子: 13.6
• 作者: M. Sakamoto

Asymmetric Synthesis of beta-Lactams Using Chiral-Memory Effect on Photochemical gamma-Hydrogen Abstraction by Thiocarbonyl Group

利用硫代羰基光化学夺取γ-氢的手性记忆效应不对称合成β-内酰胺

• 发表时间: 2008
• 期刊: Chem. Commun. 2008
• 作者: 大坪徹夫;他;大坪 徹夫;Masami SAKAMOTO;Masami SAKAMOTO;Masami SAKAMOTO
• 通讯作者: Masami SAKAMOTO

Development of proline derived chiral aminophoshine ligands for palladium-catalyzed asymmetric allylic alkylation

用于钯催化不对称烯丙基烷基化的脯氨酸衍生手性氨基膦配体的开发

• 发表时间: 2006
• 期刊: Yuki Gosei Kagaku Kyokaishi 64
• 作者: Takashi Mino;Youichi Tanaka;Masami Sakamoto;Tsutomu Fujita;Masami Sakamoto;Masami SAKAMOTO;Masami SAKAMOTO
• 通讯作者: Masami SAKAMOTO

有機結晶を利用した不斉反応の開発

使用有机晶体开发不对称反应

• 发表时间: 2007
• 作者: Takehiko Nishio;Nobuharu Iba Sakurai;Kaoru;Yo-ichi Hamano;Masami Sakamoto;Masami SAKAMOTO;Masami SAKAMOTO;Masami SAKAMOTO;Masami SAKAMOTO;Masami SAKAMOTO;Masami SAKAMOTO;Masami SAKAMOTO;Masami SAKAMOTO;Masami SAKAMOTO;Masami SAKAMOTO;坂本 昌巳;坂本 昌巳;坂本 昌巳;坂本 昌巳;坂本 昌巳;坂本 昌巳;坂本 昌巳;Masami SAKAMOTO
• 通讯作者: Masami SAKAMOTO

Copper-catalyzed N-arylation of amides and amines with aryl iodide using hydraz one ligands

使用腙一配体的铜催化酰胺和胺与芳基碘化物的 N-芳基化

• 发表时间: 2007
• 作者: Takehiko Nishio;Nobuharu Iba Sakurai;Kaoru;Yo-ichi Hamano;Masami Sakamoto;Masami SAKAMOTO;Masami SAKAMOTO;Masami SAKAMOTO;Masami SAKAMOTO;Masami SAKAMOTO;Masami SAKAMOTO;Masami SAKAMOTO;Masami SAKAMOTO;Masami SAKAMOTO;Masami SAKAMOTO;坂本 昌巳;坂本 昌巳;坂本 昌巳;坂本 昌巳;坂本 昌巳;坂本 昌巳;坂本 昌巳;Masami SAKAMOTO;Masami SAKAMOTO;Masami SAKAMOTO;Masami SAKAMOTO
• 通讯作者: Masami SAKAMOTO