非对称的vindoline总合成
Daisuke Kato1, Yoshikazu Sasaki, Dale L Boger
1Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
Journal of the American Chemical Society
|March 2, 2010
概括
本研究详细介绍了一种简洁的非对称 (-) - 温多林总合成方法,该合成方法采用了双重循环添加级联. 一个性替代物控制立体化学,在一个步骤中高效地构建五环核及其功能.
科学领域:
- 有机化学 有机化学
- 合成化学 合成化学
- 自然产品的合成自然产品的合成
背景情况:
- (-) - - 芬多林是重要的药品的关键化物前体.
- 复杂的自然产品的高效和立体选择性合成仍然是有机化学的一个重大挑战.
研究的目的:
- 开发一个简洁和不对称的 (-) - vindoline的总合成.
- 建立一种新的合成策略,采用双重循环添加级联来快速组装五循环核心.
主要方法:
- 一个1,3,4-oxadiazole衍生物的双重分子内 [4+2]/[3+2] 循环添加级联.
- 在绳索上使用合替代剂来控制面部选择性和绝对立体化学.
- 为功能化开发一种独特的环膨胀反应.
主要成果:
- 在单个关键步骤中成功构建了 (-) - 温多林的五环环系统.
- 引入三个环和四个C-C键,建立所有六个立体中心.
- 有效安装基本功能和Delta (6,7) 双键.
结论:
- 开发的合成策略提供了一个高效的 (-) -vindoline.路线.
- 串联循环加法级联是构建具有精确立体化学控制的复杂多环结构的强大工具.
- 这种方法为访问vindoline类似物和相关天然产品提供了一个有价值的平台.
相关概念视频
Diels–Alder Reaction Forming Cyclic Products: Stereochemistry
The Diels–Alder reaction is one of the robust methods for synthesizing unsaturated six-membered rings. The reaction involves a concerted cyclic movement of six π electrons: four π electrons from the diene and two π electrons from the dienophile.
[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction
The Diels–Alder reaction is an example of a thermal pericyclic reaction between a conjugated diene and an alkene or alkyne, commonly referred to as a dienophile. The reaction involves a concerted movement of six π electrons, four from the diene and two from the dienophile, forming an unsaturated six-membered ring. As a result, these reactions are classified as [4+2] cycloadditions.
Cyclohexenones via Michael Addition and Aldol Condensation: The Robinson Annulation
Robinson annulation is a base-catalyzed reaction for the synthesis of 2-cyclohexenone derivatives from 1,3-dicarbonyl donors (such as cyclic diketones, β-ketoesters, or β-diketones) and α,β-unsaturated carbonyl acceptors. Named after Sir Robert Robinson, who discovered it, this reaction yields a six-membered ring with three new C–C bonds (two σ bonds and one π bond).
Diels–Alder Reaction Forming Bridged Bicyclic Products: Stereochemistry
Diels–Alder reactions between cyclic dienes locked in an s-cis configuration and dienophiles yield bridged bicyclic products.
Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
Catalytic hydrogenation of alkenes is a transition-metal catalyzed reduction of the double bond using molecular hydrogen to give alkanes. The mode of hydrogen addition follows syn stereochemistry.
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
Cycloaddition Reactions: Overview
Cycloadditions are one of the most valuable and effective synthesis routes to form cyclic compounds. These are concerted pericyclic reactions between two unsaturated compounds resulting in a cyclic product with two new σ bonds formed at the expense of π bonds. The [4 + 2] cycloaddition, known as the Diels–Alder reaction, is the most common. The other example is a [2 + 2] cycloaddition.


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