强和封闭的酸使简单的Divinyl的催化不对称纳扎罗夫循环
Jie Ouyang1, Jennifer L Kennemur1, Chandra Kanta De1
1Max-Planck-Institut für Kohlenforschung , Kaiser-Wilhelm-Platz 1 , 45470 Mülheim an der Ruhr , Germany.
Journal of the American Chemical Society
|February 16, 2019
概括
这项研究引入了一种新的催化不对称的纳扎罗夫循环制造方法,用于制造环. 该工艺使用强的二酸Brønsted酸,实现高产量和对纯净产品的选择性.
科学领域:
- 有机化学
- 不对称的催化
背景情况:
- 纳扎罗夫循环化是合成环的关键反应.
- 开发高效的不对称方法对这种转换至关重要,
研究的目的:
- 报告一种简单的,非循环的,替代的Divinyl的新型催化不对称Nazarov循环.
- 为了证明新开发的强和封闭的 Brønsted 酸在这种转化中的有用性.
主要方法:
- 使用强度和局限性 Brønsted 酸作为催化剂.
- 使用简单的,非循环的,基替代的二维尼尔基作为基质.
主要成果:
- 成功合成单环环,产量很好.
- 在循环化产品中实现了优异的区域,度和反选择性.
- 证明了获得的纯环素的化学功效.
结论:
- 开发的催化系统提供了一条有效的途径,使其成为纯环素.
- 强度和局限性 Brønsted 酸是对不对称的纳扎罗夫循环的有效催化剂.
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A titration is carried out for 25.00 mL of 0.100 M HCl (strong acid) with 0.100 M of a strong base NaOH. The pH at different volumes of added base solution can be calculated as follows:
(a) Titrant volume = 0 mL. The solution pH is due to the acid ionization of HCl. Because this is a strong acid, the ionization is complete and the hydronium ion molarity is 0.100 M. The pH of the solution is then:
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