Reductive amination of various ketones and aldehydes by transferhydrogenation under aqueous conditions has been developed, by using cyclometallated iridium complexes as catalysts and formate as hydrogen source. The pH value of the solution is shown to be critical for a high catalytic chemoselectivity and activity, with the best pH value being 4.8. In comparison with that in organic solvents, the reductive
Chemoselective Reductive Amination of Aldehydes and Ketones by Dibutylchlorotin Hydride-HMPA Complex
作者:Toshihiro Suwa、Erika Sugiyama、Ikuya Shibata、Akio Baba
DOI:10.1055/s-2000-6273
日期:——
Reductive amination of various aldehydes and ketones has been performed effectively by pentacoordinate chloro-substituted tin hydride complex, Bu2SnClH-HMPA. The tin reagent worked particularly well for the case using weakly basic aromatic amines as starting substrates. Stoichiometric amounts of a substrate and a reducingagent were adequate for the reaction. The Sn-Cl bond in the complex plays an
Chemoselective Reductive Aminations in Aqueous Nanoreactors Using Parts per Million Level Pd/C Catalysis
作者:Ruchita R. Thakore、Balaram S. Takale、Gianluca Casotti、Eugene S. Gao、Henry S. Jin、Bruce H. Lipshutz
DOI:10.1021/acs.orglett.0c02156
日期:2020.8.21
water between aldehydes or ketones and amines occurs smoothly within the hydrophobic cores of nanomicelles, resulting in imine formation that is subject to subsequent reduction leading, overall, to reductive amination. This micellar technology enables the synthesis of several types of pharmaceuticals, a new procedure that relies on only 2000 ppm (0.20 mol %) palladium from commercially available Pd/C. A
pH-Mediated Selective Synthesis of N-Allylic Alkylation or N-Alkylation Amines with Allylic Alcohols via an Iridium Catalyst in Water
作者:Nianhua Luo、Yuhong Zhong、Hongling Shui、Renshi Luo
DOI:10.1021/acs.joc.1c01930
日期:2021.11.5
Amination of allylic alcohols is an effective approach in the facile synthesis of N-allylic alkylation or N-alkylationamines. Recently, a series of catalysts were devised to push forward this transformation. However, current synthetic methods are typically limited to achieve either N-allylic alkylation or N-alkylation products via a certain catalyst. In this article, a pH-mediated selective synthesis of N-allylic
作者:Kai Chen、Qi-Kai Kang、Yuntong Li、Wen-Qiang Wu、Hui Zhu、Hang Shi
DOI:10.1021/jacs.1c12622
日期:2022.1.26
availability of both phenols and amines, aniline synthesis through direct coupling between these starting materials would be extremely attractive. Herein, we describe a rhodium-catalyzed amination of phenols, which provides concise access to diverse anilines, with water as the sole byproduct. The arenophilic rhodium catalyst facilitates the inherently difficult keto–enol tautomerization of phenols by means of