carboxylic acids, such as benzoic acid, boost the activity of N-heterocyclic carbene (NHC) catalysts in the oxidativeesterification of aldehydes. A simple and efficient protocol for the transformation of a wide range of sterically hindered α- and β-substituted aliphatic aldehydes/enals, catalyzed by a novel and readily accessible N-Mes-/N-2,4,6-trichlorophenyl 1,2,4-triazolium salt, and benzoic acid as co-catalyst
An efficient oxidative NHC-catalyzed one-step transformation of (S)- or (R)-8-oxocitronellal to nepetalactone (NL) in enantio- and diastereomerically pure form has been developed. Several new and "easy to make" N-Mes- or N-Dipp-substituted 1,2,4-triazolium salts carrying nitroaromatic groups on N1 were synthesized and evaluated as precatalysts in combination with base and stoichiometric organic oxidant
Metal-free aminoamidiniumation employing N-iodosuccinimide: facile syntheses of bicyclic imidazolidiniums and cyclic vicinal diamines
作者:Jun Zhang、Gengtao Zhang、Weijie Wu、Xuejun Zhang、Min Shi
DOI:10.1039/c4cc07082h
日期:——
NIS-mediated aminoamidiniumation has been developed for the syntheses of bicyclic imidazolidinium salts, which could be readily converted into 2-substituted pyrrolidine and indoline diamines.
Facile Synthesis of Phosphaamidines and Phosphaamidinates using Nitrilium Ions as an Imine Synthon
作者:Tom van Dijk、Sebastian Burck、Mark K. Rong、Amos J. Rosenthal、Martin Nieger、J. Chris Slootweg、Koop Lammertsma
DOI:10.1002/anie.201405027
日期:2014.8.18
Readily accessible nitrilium triflates are convenient imine building blocks for the expedient synthesis of a novel class of 1,3‐P,N ligands as demonstrated for the reaction with primary phosphanes. This procedure allows variation of all substituents. X‐ray crystal structures are reported for nitrilium ions, phosphaamidines, and three phosphaamidinate complexes. The lithium phosphaamidinate is N coordinated
Reactivity Study of Imino-<i>N</i>-Heterocyclic Carbene Palladium(II) Methyl Complexes
作者:Anna C. Badaj、Gino G. Lavoie
DOI:10.1021/om400533d
日期:2013.8.26
Neutral and cationic palladium(II) complexes containing three different heteroditopic bis(aryl)-substituted imino-N-heterocyclic carbene ligands have been synthesized and structurally characterized. Modifications made to the substituent at the iminic carbon allow for independent tuning of the steric and electronic environment around the metal center. The nature of this substituent profoundly affects