快速水反应剂:电子和酸/效应在生物pH下强烈影响速率
Eric T Kool1, Do-Hyoung Park, Pete Crisalli
1Department of Chemistry, Stanford University , Stanford, California 94305-5080, United States.
Journal of the American Chemical Society
|November 15, 2013
概括
化物,化物和化物与附近的酸基团反应更快,形成化物. 这种加快的反应速度比应变促进的循环添加更快,为化学合成提供了新的可能性.
科学领域:
- 有机化学 有机化学
- 化学动力学 化学动力学
背景情况:
- 酸的形成是有机化学中的一个关键反应.
- 了解加速化形成的因素对于合成应用至关重要.
研究的目的:
- 为了研究化形成的动力学.
- 为了确定邻近的酸基团对反应速率的影响.
主要方法:
- 动力学研究是在pH7.4的水性缓冲剂中进行的.
- 测试了结构上不同的化物,化物和化物.
主要成果:
- 与邻近的酸基团一起的碳烯化合物表现出加快的化形成率.
- 与邻近的碳酸组一起的氨酸化合物也显示了加速反应速率.
- 最快的组合的速率常数达到2-20M(-1) s(-1),超过了应变促进的循环添加的速度常数.
结论:
- 邻近的酸基团显著加快了酸形成动力学.
- 观察到的速率与其他生物对等反应相竞争或比其他生物对等反应快.
- 这一发现对开发新的化学结合策略有影响.
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