Gold-catalyzed tandem reactions of amide–aldehyde–alkyne coupling and cyclization-synthesis of 2,4,5-trisubstituted oxazoles
作者:Pierre Querard、Simon A. Girard、Nick Uhlig、Chao-Jun Li
DOI:10.1039/c5sc02933c
日期:——
We report the first cationic gold(I)-catalyzed one-pot reaction of amide, alkyne and aldehyde followed by cyclization, to successfully access highly substituted oxazoles derivatives in good yields. A single catalyst allows...
Catalytic Three-Component Domino Reaction for the Preparation of Trisubstituted Oxazoles
作者:Henrik v. Wachenfeldt、Philipp Röse、Filip Paulsen、Nagarajan Loganathan、Daniel Strand
DOI:10.1002/chem.201300019
日期:2013.6.10
end, an efficient gold‐catalyzed three‐component domino reaction to form oxazoles directly from imines, alkynes, and acid chlorides is presented. The reaction proceeds in a single synthetic step by using a gold(III)–N,N′‐ethylenebis(salicylimine) (salen) catalyst to give trisubstituted oxazoles in up to 96 % yield. The substrate scope, a mechanistic study exploring the role of the gold catalyst, and the
Brønsted Acid-Catalyzed Propargylation/Cycloisomerization Tandem Reaction: One-Pot Synthesis of Substituted Oxazoles from Propargylic Alcohols and Amides
An efficient one-pot propargylation/cycloisomerization tandem process has been developed for the synthesis of substituted oxazole derivatives from propargylic alcohols and amides with use of p-toluenesulfonic acid monohydrate (PTSA) as a bifunctional catalyst. This method provides a rapid and efficient access to substituted oxazoles.
we report that, undermicrowave irradiation, the CeCl3·7H2O/NaI/I2 system is capable of promoting a 5-exo-dig cyclization of propargyl amides with good functional group tolerance. The microwave reactor also provides a more convenient and safer method for heating the reaction. This methodology represents a straightforward CeCl3·7H2O/NaI/I2 promoted cyclization using microwave irradiation to accomplish
A cesium carbonate promoted, transition metal and halogen‐free 5‐exo‐dig type cyclization reaction for the synthesis of oxazoles and imidazoles has been developed.