在Trit-tert-butylphosphine Palladium (II) 复合体上进行静态测量和催化-基合
Devin M Ferguson1, James R Bour1, Allan J Canty2
1Department of Chemistry, University of Michigan , 930 N University Avenue, Ann Arbor, Michigan 48109, United States.
研究人员研究了三甲基 (CF3) 和五乙基 (CF2CF3) 与的合. 他们发现CF3合产生了副产品,但CF2CF3合避免了这一点,从而实现了新的化方法.
科学领域:
- 有机金属化学
- 化学
- 催化剂
背景情况:
- 在有机合成中,催化交叉合反应至关重要.
- 将基 (如CF3和CF2CF3) 纳入有机分子是具有挑战性的,但对于药物和材料科学来说很重要.
- 之前的三甲基化方法往往产生低产量或副作用.
研究的目的:
- 调查复合体中的-基合机制.
- 了解和克服三甲基 (CF3) 合反应的局限性.
- 开发有效的催化方法,用于五甲基化 (CF2CF3).
主要方法:
- 在 (II) 复合体上对-基合的立体测量研究.
- 密度函数理论 (DFT) 计算以阐明反应机制.
- 对副产品形成途径的实验研究.
- 开发和测试催化交叉合反应.
主要成果:
- 观察到快速的基-三甲基 (Ph-CF3) 合 (在80°C下<5分钟),但由于副作用的形成而受到限制.
- 副产品归因于易于从3坐标Pd (II) 中间体中消除的α-.
- 从CF3转换为CF2CF3连接物成功绕过了不需要的α-清除途径.
- 确定Pd(PtBu3) 2是一种有效的催化剂,可以将基与TMSCF2CF3合起来.
结论:
- 在催化三甲基化中,α-的排出是关键的挑战.
- 五乙烯 (CF2CF3) 连接物更稳定,避免有问题的副作用.
- 这项研究为设计选择性 perfluoroalkylation 的催化剂提供了关键的见解.
- 成功开发了一种用于合成五乙烯的新型催化系统.
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