Fe‐Catalyzed Anaerobic Mukaiyama‐Type Hydration of Alkenes using Nitroarenes
作者:Anup Bhunia、Klaus Bergander、Constantin Gabriel Daniliuc、Armido Studer
DOI:10.1002/anie.202015740
日期:2021.4.6
Hydration of alkenes using first row transitionmetals (Fe, Co, Mn) under oxygen atmosphere (Mukaiyama‐type hydration) is highly practical for alkene functionalization in complex synthesis. Different hydration protocols have been developed, however, control of the stereoselectivity remains a challenge. Herein, highly diastereoselective Fe‐catalyzed anaerobic Markovnikov‐selective hydration of alkenes
Regiodivergent hydrosilylation, hydrogenation, [2π + 2π]-cycloaddition and C–H borylation using counterion activated earth-abundant metal catalysis
作者:Riaz Agahi、Amy J. Challinor、Joanne Dunne、Jamie H. Docherty、Neil B. Carter、Stephen P. Thomas
DOI:10.1039/c8sc05391j
日期:——
The widespread adoption of earth-abundant metal catalysis lags behind that of the second- and third-row transitionmetals due to the often challenging practical requirements needed to generate the active low oxidation-state catalysts. Here we report the development of a single endogenous activation protocol across five reaction classes using both iron- and cobalt pre-catalysts. This simple catalytic
INDIUM MEDIATED ALLYLATION OF NITRO GROUP ON NITROBENZENE DERIVATIVES IN AQUEOUS MEDIA
作者:Kyung Ho Kang、Kyung Il Choi、Hun Yeong Koh、Youseung Kim、Bong Young Chung、Yong Seo Cho
DOI:10.1081/scc-100104827
日期:2001.1
Indium mediatedallylation of nitro group was first achieved with four allylbromides in aqueous media. Nitro- benzenes bearing 3- and/or 4-substituent(s) gave mainly N,N-diallylated (I or I′) and/or N,O-diallylated (II) products by Method A. Allylation of nitrobenzenes having 2- (and 5-) substituent(s) could be achieved only with crotyl bromide by Method B.
铟介导的硝基烯丙基化首先在水性介质中用四种烯丙基溴实现。带有 3- 和/或 4- 取代基的硝基苯通过方法 A 主要得到 N,N-二烯丙基化(I 或 I')和/或 N,O-二烯丙基化 (II) 产物。 具有 2- 取代基的硝基苯的烯丙基化(和 5-) 取代基只能通过方法 B 使用巴豆基溴来实现。
An atom efficient route to N-aryl and N-alkyl pyrrolines by transition metal catalysis
作者:Supaporn Sawadjoon、Joseph S. M. Samec
DOI:10.1039/c0ob00383b
日期:——
The synthesis of N-aryl, N-tosyl, and N-alkyl pyrrolines fromallylalcohols and amines has been developed. The reaction sequence includes a palladium-catalyzed allylation step in which non-manipulated allylalcohol is used to generate the diallylated amine in good to excellent yield. An excess of allylalcohol was necessary for efficient diallylation of the amine, where the excess alcohol could be
已经开发了由烯丙醇和胺合成N-芳基,N-甲苯磺酰基和N-烷基吡咯啉的方法。反应序列包括钯催化的烯丙基化步骤,其中使用未处理的烯丙醇以良好至极佳的产率生成二烯丙基化的胺。过量烯丙醇对于胺的有效二烯丙基化是必需的,其中过量的醇可以循环三次。对于芳基和甲苯基胺,使用Pd [P(OPh)3 ] 4;对于苄基和烷基胺,使用包含Pd(OAc)2,P n Bu 3和BEt 3的催化体系。胺的电子性质和空间影响都影响烯丙基化的效率。通过(H 2 IMes)(PCy 3)Cl 2 RuCHPh催化的闭环复分解,将分离出的二烯丙基化胺转化为它们相应的吡咯啉,收率良好。开发了一个一锅反应,其中苯胺将其转化为相应的吡咯啉,而无需分离二烯丙基化的中间体。此一锅法反应已成功放大至1 mL苯胺其中分离出N-苯基吡咯啉的产率为95%。证明了分两步制备3-甲基-1-苯基吡咯啉的反应的通用性。
Synthesis of Pyrrole Derivatives from Diallylamines by One-Pot Tandem Ring-Closing Metathesis and Metal-Catalyzed Oxidative Dehydrogenation
作者:Weiqiang Chen、Jianhui Wang
DOI:10.1021/om400046r
日期:2013.3.25
A series of aryl-substituted pyrrole derivatives was synthesized from diallylamines through a ruthenium carbene catalyzed ring-closingmetathesis reaction and in situ oxidative dehydrogenation reaction catalyzed by FeCl3·6H2O or CuCl2·2H2O in the presence of O2. The reaction was mild, simple, and convenient. An oxygen atmosphere played a critical role in obtaining high conversion of substituted pyrroles