New benzimidazolium sulfonate salts have been prepared and fully characterized. They have been associated in situ with [RuCl2(p-cymene)]2 to generate efficient catalytic systems operating at 120 °C under neat conditions in the presence of potassium tert-butylate for selective N-alkylation of primary aromatic amines into secondary amines.
Visible‐Light‐Induced Cycloaddition of α‐Ketoacylsilanes with Imines: Facile Access to β‐Lactams
作者:Jian‐Heng Ye、Peter Bellotti、Tiffany O. Paulisch、Constantin G. Daniliuc、Frank Glorius
DOI:10.1002/anie.202102451
日期:2021.6.7
report the synthesis of β-lactams from α-ketoacylsilanes and imines, which proceeds via a formal [2+2] photochemical cycloaddition with in situ generation of siloxyketene. This mild and operationally simple reaction proceeds in an atom-economic fashion with broad substrate scope, including aldimines, ketimines, hydrazones, and fused nitrogen heterocycles, affording a variety of important β-lactams with satisfactory
Readily Available Primary Aminoboranes as Powerful Reagents for Aldimine Synthesis
作者:Glen P. Junor、Erik A. Romero、Xi Chen、Rodolphe Jazzar、Guy Bertrand
DOI:10.1002/anie.201814081
日期:2019.2.25
Primary aminoboranes (RNHBR2), which are readily available by spontaneous dehydrocoupling of amines and boranes cleanly react at room temperature with aldehydes to give aldimines. The overall transformation from amines to aldimines can be conveniently performed by a sequential one‐pot reaction. This synthetic strategy is especially useful for electron poor and bulky amines which are reluctant to react
was enabled by an unprecedented 1,2-boryl carbon-to-nitrogen migration. Based on the discovery of a rearrangement of an α-borylalkylamido copper intermediate to an α-borylaminoalkyl copper species through 1,2-migration of a boryl groupfromcarbon to nitrogen and copper migration fromnitrogen to carbon, we have developed a copper-catalyzed selective allylation of a wide range of aldimines and ketimines
我们报告了催化亚胺催化的一般策略,这是由前所未有的1,2-硼基碳到氮的迁移实现的。基于通过硼基从碳到氮的1,2-迁移以及铜从氮到碳的迁移将α-硼烷基烷基酰胺基铜中间体重排为α-硼烷基氨基烷基铜物种的发现,我们开发了一种铜催化的在存在B 2(pin)2和LiO t Bu的情况下,将多种醛胺和酮亚胺与烯丙基亲电试剂选择性烯丙基化。我们期望这种催化的亚胺-苯丙氨酸催化策略可能会衍生出用于合成各种功能化胺的有用方法。
CO<sub>2</sub> Activation by Lewis Pairs Generated Under Copper Catalysis Enables Difunctionalization of Imines
substrate activation modes in a catalytic circle is critical for the development of new, powerful synthetic methodologies toward complex and value-added chemicals from simple and readily available feedstocks. Here, we describe a highly selective difunctionalization of imines through incorporation of activation of CO2 by intramolecular N/B Lewis pairs into a copper catalytic cycle. Experimental and computational
在催化循环中整合不同的底物活化模式对于开发新的、强大的合成方法至关重要,这些方法可以从简单易得的原料中获得复杂和高附加值的化学品。在这里,我们描述了通过将分子内 N/B Lewis 对激活的 CO2 结合到铜催化循环中来实现亚胺的高选择性双官能化。机理方面的实验和计算研究揭示了一种α-硼烷基酰胺中间体,一种由 CN 双键硼化形成的金属酰胺基路易斯对,实现了前所未有的 固定模式,这与传统的 插入过渡金属元素形成鲜明对比债券。独特的环状硼氨基甲酸锂产品可以很容易地转化为多功能的 N-羧化 α-氨基硼酸盐。还实现了手性 N-叔丁烷亚磺酰基醛亚胺的高度非对映选择性反应。我们希望我们的发现可以通过将路易斯对化学结合到过渡金属催化中来激发选择性多组分反应的进一步发展。