Green Catalysts: Solid-Phase Peptide Carbene Ligands in Aqueous Transition-Metal Catalysis
作者:Kasper Worm-Leonhard、Morten Meldal
DOI:10.1002/ejoc.200800633
日期:2008.11
functionalized imidazolium ions containing a pyridine moiety and carboxylic acid functionality has been synthesized in solution. These compounds serve as N-heterocyclic carbene precursors and were attached to a dipeptide on solid support by means of standard peptide coupling techniques. Treatment with base generated the corresponding carbenes, which were directly complexed to palladium(II) and subsequently studied
Cellulose-Supported Copper(0) Catalyst for Aza-Michael Addition
作者:K. Reddy、Nadakudity Kumar
DOI:10.1055/s-2006-949623
日期:2006.9
Cellulose-supported copper(0) efficiently catalyzes the aza-Michael reaction of N-nucleophiles, such as amines and imidazoles with α,β-unsaturated compounds to produce the corresponding β-amino compounds and N-substituted imidazoles in excellent yields. The reactions are facile and the recovered catalyst is used for several cycles with consistent activity.
Mild and Efficient Procedure for Michael Addition of N-Heterocycles to <font>α</font>,<font>β</font>-Unsaturated Compounds Using Anhydrous K<sub>3</sub>PO<sub>4</sub> as Catalyst
Imidazole, 1,2,4-triazole, indole, and benzotriazole undergo conjugate additions with , -unsaturated carbonyl compounds in the presence of anhydrous potassium phosphate at ambient temperature to afford the corresponding Michael adducts in excellent yields.
Optically Active (Peptido-carbene)palladium Complexes: Towards True Solid-Phase Combinatorial Libraries of Transition Metal Catalysts
作者:Jakob F. Jensen、Kasper Worm-Leonhard、Morten Meldal
DOI:10.1002/ejoc.200800234
日期:2008.6.27
combinatorial solid-phase peptide chemistry to produce catalysts with enzyme-like properties of stereoselectivity, regioselectivity and even substrate selectivity. A series of new functionalised carbene precursors/donors – imidazolium salts – each containing both amino acid and carboxylic acid functionality was synthesised in solution. The readily accessible carbene precursors were incorporated within the backbones