随时可用的基于Ti的in situ催化系统用于oxo/imido异质相异解
Andrey V Rumyantsev1,2, Nikolai S Bushkov1, Margarita A Ryzhikova1,3
1A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilov str., 28, 119334 Moscow, Russia. zhizhko@ineos.ac.ru.
Dalton transactions (Cambridge, England : 2003)
|February 23, 2024
概括
一种新型的胺预催化剂支持于二氧化,有效催化化化反应. 通过氨酸激活,它表现出与明确的催化剂相当的活性,为合成各种含化合物提供了方便的替代品.
科学领域:
- 不同质的催化剂.
- 有机金属化学 有机金属化学
- 材料科学是一种材料科学.
背景情况:
- 在有机合成中,oxo/imido异构反应至关重要.
- 精确定义的支持型催化剂具有高活性,但制备起来可能很复杂.
- 可访问的预催化剂对于简化催化过程是可取的.
研究的目的:
- 为了研究四 ((diethylamide) 支持化作为成像反应的前催化剂.
- 为了评估激活支持的胺的催化性能.
- 为了比较它的活性与现有的明确的imido催化剂.
主要方法:
- 在脱氧化二氧化的基础上制备Ti(NEt2) 4的制剂.
- 用4-toluidine (TolNH2) 激活支持的胺.
- 使用IR,元素分析 (EA) 和固态NMR (1H,13C,15N,2DNMR) 的表征.
- 在各种成像反应中测试催化活性.
主要成果:
- 活性支持的胺胺, (SiO) Ti ((NEt2) 3 (1),在胺胺化过程中表现出催化活性.
- 它的性能相当于一个明确的支持的模拟催化剂,这表明在现场模拟物种的形成.
- 描述表明三胺, (SiO) Ti ((NHC6H4X) 3作为主要的表面物种,而不是拟议的imido中间体.
- 1/TolNH2系统有效地产生了胺,甲胺,乳胺基和硫胺基.
结论:
- 支持的胺系统作为一种有效且易于获得的化反应前催化剂.
- 它提供了一种方便的替代品,可以与已定义的支持等离子催化剂合成有价值的含化合物.
- 这项研究突出了胺在异质催化中的胺在二氧化支持的潜力.
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