Selective deprotection of allyl amines using palladium
摘要:
Mono and diallylamines can be cleaved using Pd(0) catalyst and 2-mercaptobenzoic acid as nucleophile. This methodology has been successfully used for the sequential deprotection of diallylamines. The yields of desallylation are good to quantitative.
Asymmetric Palladium-Catalyzed Alkene Carboamination Reactions for the Synthesis of Cyclic Sulfamides
作者:Zachary J. Garlets、Kaia R. Parenti、John P. Wolfe
DOI:10.1002/chem.201600887
日期:2016.4.18
The synthesis of cyclic sulfamides by enantioselective Pd‐catalyzed alkene carboamination reactions between N‐allylsulfamides and aryl or alkenyl bromides is described. High levels of asymmetric induction (up to 95:5 e.r.) are achieved using a catalyst composed of [Pd2(dba)3] and (S)‐Siphos‐PE. Deuterium‐labelling studies indicate the reactions proceed through syn‐aminopalladation of the alkene and
Chiral Counteranions in Asymmetric Transition-Metal Catalysis: Highly Enantioselective Pd/Brønsted Acid-Catalyzed Direct α-Allylation of Aldehydes
作者:Santanu Mukherjee、Benjamin List
DOI:10.1021/ja074678r
日期:2007.9.1
Pd/chiral acid-catalyzed α-allylation of α-branched aldehydes with an allyl amine as the allylating species that creates all-carbonquaternary stereogenic centers in high yields and enantioselectivities. To our knowledge, this is the first time that a chiral anionic ligand is applied for achieving asymmetric induction in a palladium-catalyzedallylicalkylation reaction.
Visible-Light-Mediated Umpolung Reactivity of Imines: Ketimine Reductions with Cy<sub>2</sub>NMe and Water
作者:Rui Wang、Mengyue Ma、Xu Gong、Grace B. Panetti、Xinyuan Fan、Patrick J. Walsh
DOI:10.1021/acs.orglett.8b00778
日期:2018.4.20
carbanionic reactivity of imines mediated by photoredox catalysis is demonstrated. The umpolung imine reactivity is exemplified by proton abstraction from water as a key step in the reduction of benzophenone ketimines to amines (up to 98% yield). Deuterium is introduced into amines efficiently using D2O as an inexpensive deuterium source (≥95% D ratio). The mechanism of this unusual transformation
Carbonylative C−C Bond Activation of Electron-Poor Cyclopropanes: Rhodium-Catalyzed (3+1+2) Cycloadditions of Cyclopropylamides
作者:Andrew G. Dalling、Takayuki Yamauchi、Niall G. McCreanor、Lydia Cox、John F. Bower
DOI:10.1002/anie.201811460
日期:2019.1.2
Rh‐catalyzed carbonylative C−C bond activation of cyclopropylamides generates configurationally stable rhodacyclopentanones that engage tethered alkenes in (3+1+2) cycloadditions. These studies provide the first examples of multicomponent cycloadditions that proceed through C−C bond activation of “simple” electron poor cyclopropanes.