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一个交叉结合的enediyne的阳离子循环

Lior Eshdat¹, Harald Berger, Henning Hopf

¹Department of Organic Chemistry, The Hebrew University of Jerusalem, 91904 Jerusalem, Israel.

Journal of the American Chemical Society

|April 11, 2002

概括

研究人员证明了交叉结合的基因的新型阳离子循环,在减少条件下形成五个成员的环. 这种方法克服了传统的伯格曼循环芳香化的局限性,通过产生Hückel数的pi电子.

科学领域:

有机化学有机化学
合成化学合成化学

背景情况:

交叉结合的基因通常不会经历伯格曼循环芳香化,因为pi电子不足.
减少条件可以通过形成具有Hückel pi电子数量的产物来实现循环.

研究的目的:

为了说明和演示交叉结合的enediynes的阳离子循环.
通过这种新的方法,通过这种新的方法来形成一个五个成员的环.

主要方法:

使用降低9-9H-二甲基 (基) -3-基-1-基乙烯-2-基) -9H-基 (3).
产生9-9H-的二离子,即9-9--3,4-二烯cyclopenta-2,4-dienylidene) -9H- (4-).
用氧化的氧化.

主要成果:

成功演示了一个交叉结合的enediyne的阳离子循环.
一个五个环的形成,其中包含一个环丁基碎片.
一种不稳定的富拉产品的分离 (4).

结论:

在还原条件下的阳离子循环是交叉结合的氨酸的可行策略.
这种方法克服了伯格曼循环芳香化的电子限制.
这项研究首次呈现了一种交叉结合的enediyne的阳离子循环,从而产生了五个成员的环.

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