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Analysis of the factors that govern stereoselectivity in the reactions of oxocarbenium ion intermediates: The role of neighboring-group participation and the correlation between nucleophile strength and stereoselectivity.

机译：氧碳鎓离子中间体反应中控制立体选择性的因素分析：邻基参与的作用以及亲核试剂强度与立体选择性之间的关系。

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The chemical synthesis of oligosaccharides and natural products containing carbohydrate moieties is often hampered by the inability to form glycosidic linkages in a stereoselective manner. This dissertation discusses investigations into the factors that control stereoselectivity in additions to endocyclic oxocarbenium ion intermediates and related model systems. Chapter one focuses on the role of neighboring-group participation by sulfur substituents. Spectroscopic evidence for the formation of low energy sulfonium ion intermediates is discussed, as are data indicating that nucleophilic addition occurs through higher energy oxocarbenium ion intermediates. Chapter two details the correlation between nucleophilicity and stereoselectivity in the reactions of alcohol nucleophiles and oxocarbenium ion intermediates. The erosion of selectivity with increasing reactivity is consistent with rates of nucleophilic addition that approach the diffusion limit. Chapter three discusses the extension of the diffusion limit hypothesis to reactions of allyl Grignard reagents and carbonyl compounds.

机译：寡糖和含有碳水化合物部分的天然产物的化学合成常常由于不能以立体选择性的方式形成糖苷键而受到阻碍。本文讨论了除环氧羰基离子中间体及相关模型系统外，还控制立体选择性的因素。第一章着重于硫取代基参与邻近基团的作用。讨论了形成低能sulf离子中间体的光谱证据，以及表明亲核加成通过高能氧碳鎓离子中间体发生的数据。第二章详细介绍了醇类亲核体与氧碳鎓离子中间体反应中亲核性与立体选择性之间的关系。随着反应活性的增加，选择性的侵蚀与接近扩散极限的亲核加成速率一致。第三章讨论了扩散极限假设对烯丙基格氏试剂与羰基化合物反应的扩展。

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作者
Beaver, Matthew Grant.;
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作者单位

University of California, Irvine.;

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授予单位 University of California, Irvine.;
学科 Chemistry Organic.
学位 Ph.D.
年度 2010
页码 441 p.
总页数 441
原文格式 PDF
正文语种 eng
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2. The unusual 1,4-chelation-controlled nucleophilic addition to aldehydes with high stereoselectivity. A systematic study of stereoselectivity in the addition reaction of carbon nucleophiles to cis-substituted cyclopropanecarbaldehydes [J] . Kazuta Y, Abe H, Yamamoto T, Tetrahedron . 2004,第31期

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3. Stereoelectronic Model To Explain Highly Stereoselective Reactions of Seven-Membered-Ring Oxocarbenium-Ion Intermediates [J] . Beaver Matthew G., Buscagan Trixia M., Lavinda Olga, Angewandte Chemie . 2016,第5期

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机译：硝基苯乙烯与亚硝基加成反应的硅烷醇基氢键催化剂的合成与评价。烯丙基硅烷作为2,3'-吡咯烷基乙烯基螺氧基吲哚的立体选择性形成的温和有效亲核试剂。
6. Stereoelectronic Model to Explain Highly Stereoselective Reactions of Seven-membered Ring Oxocarbenium Ion Intermediates [O] . Dr. Matthew G. Beaver, Trixia M. Buscagan, Olga Lavinda, -1

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机译：解释七元环氧碳鎓离子中间体的高度立体选择性反应的立体电子模型

Analysis of the factors that govern stereoselectivity in the reactions of oxocarbenium ion intermediates: The role of neighboring-group participation and the correlation between nucleophile strength and stereoselectivity.

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