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对可调节封闭度和酸度的伊米多二酸酸的统一方法
Sebastian A Schwengers1, Chandra Kanta De1, Oleg Grossmann1
1Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany.
Journal of the American Chemical Society
|September 3, 2021
概括
我们开发了一种简单的合成新型二酸Brønsted酸. 这些催化剂具有可调节的酸度和有限的活性位点,使高度反选择性反应能够超越常见的超酸性反应.
科学领域:
- 有机合成
- 催化剂
- 酸性化学
背景情况:
- 基于二化物 (IDP) 的布伦斯特德酸是有价值的催化剂.
- 开发高效的合成路径到多种IDP支架仍然是一个挑战.
- 可调节的酸度和活动部位封闭是先进的催化应用的关键特征.
研究的目的:
- 建立一个高效和操作简单的单瓶合成基于二酸的布伦斯特德酸.
- 探索这些新型酸催化剂的催化潜力,特别是在酶选择性转化中.
- 设计和合成具有增强反应性的新型超酸催化剂.
主要方法:
- 通过连续化物替代六二盐的单瓶合成.
- 合成的 imidodiphosphates (IDP),iminoimidodiphosphates (iIDP) 和 imidodiphosphorimidates (IDPi) 的特征
- 在硫化和甲基化反应中评估催化剂的酸度 (pKa) 和性能.
主要成果:
- 快速访问可调节酸度的IDP,iIDP和IDPI支架 (pKa在MeCN中为~11至<2).
- 使用结构有限的IDP催化剂,证明高度选择性硫化 (>95:5er).
- 开发一种超酸性胺二酸 (胺二酸) 催化剂,其反应性超过三甲硫酸.
- 通过使用甲醇作为IDPii催化剂的电友,成功地α-甲基化了一种西乙醇.
结论:
- 开发的方法提供了一系列基于二酸的布伦斯特德酸.
- 这些催化剂具有可调节的特性,并使具有挑战性的反选择性转换成为可能.
- 新型的IDPii超酸体表现出异常的反应性,为酸催化开辟了新的途径.
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