Minimization of Back‐Electron Transfer Enables the Elusive sp
<sup>3</sup>
C−H Functionalization of Secondary Anilines
作者:Huaibo Zhao、Daniele Leonori
DOI:10.1002/anie.202100051
日期:2021.3.29
Anilines are some of the most used class of substrates for application in photoinduced electron transfer. N,N‐Dialkyl‐derivatives enable radicalgenerationα to the N‐atom by oxidation followed by deprotonation. This approach is however elusive to monosubstituted anilines owing to fast back‐electron transfer (BET). Here we demonstrate that BET can be minimised by using photoredox catalysis in the presence
One‐Pot Transfer Hydrogenation Reductive Amination of Aldehydes and Ketones by Iridium Complexes “on Water”
作者:Lu Ouyang、Yanping Xia、Jianhua Liao、Renshi Luo
DOI:10.1002/ejoc.202001097
日期:2020.10.31
An efficient and practical one-pot transfer hydrogenation reductive amination of aldehydes and ketones with amines has been developed by using iridium complexes as catalysts and formic acid as hydrogen source in aqueous, providing an environmentalfriendly methodology for the construction of a wide range of functionalized amine compounds in excellent yields (80%~95%) This effective methodology can
Direct and indirect reductive amination of aldehydes and ketones with solid acid-activated sodium borohydride under solvent-free conditions
作者:Byung Tae Cho、Sang Kyu Kang
DOI:10.1016/j.tet.2005.04.039
日期:2005.6
A simple and convenient procedure for reductive amination of aldehydes and ketonesusingsodiumborohydride activated by boric acid, p-toluenesulfonic acid monohydrate or benzoic acid as reducing agent under solvent-free conditions is described.
Mechanistic Studies of Hydride Transfer to Imines from a Highly Active and Chemoselective Manganate Catalyst
作者:Frederik Freitag、Torsten Irrgang、Rhett Kempe
DOI:10.1021/jacs.9b05024
日期:2019.7.24
highly active and chemoselective manganese catalyst for the hydrogenation of imines. The catalyst has a large scope, can reduce aldimines and ketimines, and tolerates a variety of functional groups, among them hydrogenation sensitive examples such as an olefin, a ketone, nitriles, nitro groups and an aryl iodo substituent or a benzyl ether. We could investi-gate the transfer step between imines and the
我们介绍了一种用于亚胺加氢的高活性和化学选择性锰催化剂。该催化剂适用范围广,可还原醛亚胺和酮亚胺,可耐受多种官能团,其中对氢化敏感的例子如烯烃、酮、腈、硝基和芳基碘取代基或苄基醚。我们可以详细研究亚胺和氢化物配合物之间的转移步骤。我们发现配体的双重去质子化是必不可少的,过量的碱不会导致转移步骤中的更高速率。我们将实际的加氢催化剂鉴定为 K-Mn-双金属物种,并且可以通过 X 射线分析获得氢化物转移后形成的 K-Mn 配合物的结构。核磁共振实验表明氢化物转移是一个明确定义的反应,这是亚胺的一级,双金属(K-Mn)氢化物的一级,并且速率与钾碱的浓度无关。我们提出了一种外球机制,其中质子似乎不参与速率确定步骤,导致底物中的瞬态带负电荷的氮原子与 HOtBu(2-methylpropan-2-ol)迅速反应以产生胺。这是基于几个观察结果,例如反应速率不依赖于 HOtBu 浓度,没有可观察到的锰酰胺