直接和高度区域选择性和对β-二基的反选择性合
Wesley A Chalifoux1, Samuel K Reznik, James L Leighton
1Department of Chemistry, Columbia University, New York, New York 10027, USA.
Nature
|July 6, 2012
概括
对于子,对合成复杂分子至关重要,现在可以实现β-二基子的酶选择性合. 这种新方法克服了反应性挑战,扩大了对有价值的性三级碳醇的获取.
科学领域:
- 有机化学 有机化学
- 不对称的合成方法
背景情况:
- 基的酶选择性合是创造性三级碳醇的关键.
- 现有的方法仅限于简单的子,阻碍了复杂分子的合成.
- 需要适用于功能复杂子的方法.
研究的目的:
- 开发一种方法来对β-二基子进行对抗选择性合.
- 为了使复杂的三级碳醇从具有挑战性的基质合成.
- 在不对称合成中克服β-二基的固有反应性.
主要方法:
- 使用β-二基的乙醇形式进行布伦斯特德酸激活.
- 开发了一种操作上简单,直接,区域选择性和酶选择性化协议.
- 通过特定的激活策略克服β-二基的核友性.
主要成果:
- 取得了成功的β-二基的对抗选择性合.
- 产生了更广泛的基丰富和功能复杂的三级碳醇.
- 证明了β-二基的新型反应途径,挑战了已有的化学原理.
结论:
- 开发的方法显著扩大了类合的范围.
- 为复杂的合成提供了对有价值的性构建块的轻松访问.
- 代表了理解和利用β-二甲反应性的突破.
相关概念视频
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Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn stereochemistry.
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