Highly pH-Dependent Chemoselective Transfer Hydrogenation of alpha,beta-Unsaturated Aldehydes in Water
Highly pH-Dependent Chemoselective Transfer Hydrogenation of alpha,beta-Unsaturated Aldehydes in Water
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水中 α,β-不饱和醛的高度 pH 依赖性化学选择性转移氢化
DOI：
10.1021/acs.organomet.9b00353
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发表时间：
2019
期刊：
影响因子：
2.8
通讯作者：
Luo Renshi
中科院分区：
文献类型：
--
作者：
Luo Nianhua;Liao Jianhua;Ouyang Lu;Wen Huiling;Liu Jitian;Tang Weiping;Luo Renshi
在水中实现了α，β-不饱和醛的pH依赖选择性Ir催化加氢反应。在低pH条件下，以HCOOH为氢化物供体时，只生成不饱和醇类产物，而在高pH条件下，以HCOONa为氢化物给体，则优先生成饱和醇类产物。α，β-不饱和醛的芳基上的各种官能团，包括富电子取代基和贫电子取代基，都可以被容忍，从而提供了高TOF值、高产率的相应产品。具有脂肪取代基的α，β不饱和醛的选择性和产率也很高。我们的机理研究表明，pH值对化学选择性是至关重要的。
The pH-dependent selective Ir-catalyzed hydrogenation of α,β-unsaturated aldehydes was realized in water. Using HCOOH as the hydride donor at low pH, the unsaturated alcohol products were obtained exclusively, while the saturated alcohol products were formed preferentially by employing HCOONa as the hydride donor at high pH. A wide range of functional groups including electron-rich as well as electron-poor substituents on the aryl group of α,β-unsaturated aldehydes can be tolerated, affording the corresponding products in excellent yields with high TOF values. High selectivity and yields were also observed for α,β-unsaturated aldehydes with aliphatic substituents. Our mechanistic investigations indicate that the pH value is critical to the chemoselectivity.