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Asymmetric Synthesis of Five-membered Compounds by Transition Metal-Catalyzed Asymmetric Cyclizations of Enyne Systems

过渡金属催化烯炔体系不对称环化合成五元化合物

基本信息

批准号：
11672113
负责人：
HIROI Kunio
金额：
$ 2.37万
依托单位：
Tohoku Pharmaceutical University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2000
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11672113/
关键词：
catalytic asymmetric synthesis asymmetric cyclization palladium catalyst chiral sulfinyl group chiral ligand enantioselectivity organosulfur group cobalt catalyst 不斉環化異性化反応

项目摘要

Enyne compounds undergo cyclization reactions, upon treatment with transition metal catalysts such as palladium, nickel, cobalt, rhodium and so on. The use of chiral auxiliaries involved in the systems or chiral ligands provides a new strategy for asymmetric synthesis of cyclic compounds. Our recent results of asymmetric cyclizations with transition metals along these lines are as follows.1. The use of symmetric substrates involving two olefinic parts with the same substituents and an yne group in palladium-catalyzed reactions provided enantiotopic differentiating reaction products by using chiral sulfinyl or (S)-proline-derived groups involed in the substrates or chiral ligands.2. The palladium-catalyzed asymmetric cycloisomerizations were applicable to 1,6-enyne systems involving chiral sulfinyl, (S)-proline or (S)-tetrahydroisoquinoline-derived groups in the systems as chiral auxiliaries or using chiral ligands, providing a new entry to chiral five-membered compounds. Introduction o … More f a carboxyl group into the 1,6-enyne substrates provided higher diastereo- or enantioselectivity, presumably due to stereocontrol of the conformation of the resultant intermediary palladium complexes by coordination of the carboxyl groups to the palladium catalysts involved in the systems.3. The first catalytic asymmetric Pauson-Khand reaction has been developed by using chiral phosphine ligands, in which dramatic effects of the substituents were observed in achieving high enantioselectivity. Introduction of chiral organosulfur functionality such as sulfinyl or sulfinamide groups has been attempted. Slightly low efficiency was observed with the chiral organosulfur groups. Participation of organosulfur functionality was also revealed by the use of (S)-methionine-derived substrates for the Pauson-Khand reactions. The role of the sulfenyl groups involved in the chiral substrates derived from (S)-methionine and (S)-S-methylcystein in the cobatlt catalysis was reveiled in comparison with the results obtained from the substrates without organosulfur functionality, derived from (S)-norvaline and (S)-norleucine. The structure of the product was determined by the X-ray christallographic analysis. The reaction mechanism is proposed on the basis of the stereochemical results obtained.4. The stereochemistry of the palladium-catalyzed conversion of (1,3-butadienyl) cyclopentene derivatives into cyclopentenes was determined. The participation of the chiral sulfinyl groups in the palladium catalysis was revealed by the comparison with the stereochemical results between two geometrical isomers of the chiral vinylic sulfoxides employed as starting substrates. Less

烯炔类化合物在钯、镍、钴、铑等过渡金属催化剂作用下发生环化反应，手性助剂或手性配体的引入为不对称合成环状化合物提供了新的策略。我们最近的研究结果如下：1.过渡金属沿着这些路线的不对称环化反应.在钯催化的反应中使用对称底物，包括两个具有相同取代基的烯烃部分和一个炔基，通过使用底物或手性配体中涉及的手性亚磺酰基或（S）-脯氨酸衍生的基团，提供了对映异构体差异化的反应产物.钯催化的不对称环异构化反应适用于手性亚磺酰基、（S）-脯氨酸或（S）-四氢异喹啉衍生基团作为手性助剂或手性配体参与的1，6-烯炔体系，为手性五元化合物的合成提供了新的途径。导言 ...更多信息将羧基引入1，6-烯炔底物中提供了更高的非对映体或对映体选择性，这可能是由于通过羧基与体系中所涉及的钯催化剂的配位来立体控制所得中间体钯络合物的构象.首次利用手性膦配体催化不对称Pauson-Khand反应，发现取代基的显著作用对反应具有很高的对映选择性。已经尝试引入手性有机硫官能团，例如亚磺酰基或亚磺酰胺基团。观察到手性有机硫基团的效率略低。有机硫官能团的参与也通过使用（S）-甲硫氨酸衍生的底物用于Pauson-Khand反应而揭示。通过与来自（S）-正缬氨酸和（S）-正亮氨酸的不含有机硫官能团的底物的结果进行比较，揭示了来自（S）-甲硫氨酸和（S）-S-甲基半胱氨酸的手性底物中所涉及的硫基在钴催化中的作用。用X射线衍射分析确定了产物的结构。根据立体化学结果提出了反应机理.测定了钯催化1，3-丁二烯基环戊烯衍生物转化为环戊烯的立体化学。通过与用作起始底物的手性乙烯基亚砜的两种几何异构体之间的立体化学结果的比较，揭示了手性亚磺酰基在钯催化中的参与。少