Reductive Amination/Cyclization of Keto Acids Using a Hydrosilane for Selective Production of Lactams versus Cyclic Amines by Switching of the Indium Catalyst
作者:Yohei Ogiwara、Takuya Uchiyama、Norio Sakai
DOI:10.1002/anie.201509465
日期:2016.1.26
amines by reductive amination, using an indium/silane combination. This relatively benign and safe catalyst/reductant system tolerates the use of a variety of functional groups, especially ones that are reduction‐sensitive. A direct switch from synthesizing lactams to synthesizing cyclic amines is achieved by changing the catalyst from In(OAc)3 to InI3. This conversion occurs by further reduction of the
Levulinic acid (LA) is transformed into pyrrolidinones by formic acid in DMSO without a catalyst. Mechanistic studies suggest the involvement of an iminium intermediate and a rate-limiting hydride transfer step.
Cobalt‐Catalyzed Selective Transformation of Levulinic Acid and Amines into Pyrrolidines and Pyrrolidinones using Hydrogen
作者:Yixiao Pan、Zhenli Luo、Ji Yang、Jiahong Han、Jianbo Yang、Zhen Yao、Lijin Xu、Peng Wang、Qian Shi
DOI:10.1002/adsc.202200578
日期:2022.8.16
Cobalt-catalyzed selectivetransformation of levulinicacid and primary amines into pyrrolidines and pyrrolidinones under H2 has been developed. The catalyst system consisting of Co(NTf2)2, 1,1,1-tris(di(4-methoxyphenyl)phosphinomethyl) ethane ((p-anisyl)triphos) and Me3SiOTf works well for the synthesis of pyrrolidines via reductive amination/cyclization/deoxygenative reduction of amide, and using Co(NTf2)2/1
Levulinic acid (LA) is transformed into pyrrolidinones via iridium-catalysed reductive amination using formic acid as the hydrogen source under aqueous conditions. The catalytic system is the most active and performs under the mildest conditions ever reported for the reductive amination of LA.