1214921-68-2Relevant academic research and scientific papers
Cyclization of propargylic amides: Mild access to oxazole derivatives
Weyrauch, Jan P.,Hashmi, A. Stephen K.,Schuster, Andreas,Hengst, Tobias,Schetter, Stefanie,Littmann, Anna,Rudolph, Matthias,Hamzic, Melissa,Visus, Jorge,Rominger, Frank,Frey, Wolfgang,Bats, Jan W.
, p. 956 - 963 (2010)
The substrate scope, the mechanistic aspects of the gold-catalyzed oxazole synthesis, and substrates with different aliphatic, aromatic, and functional groups in the side chain were investigated. Even molecules with several propargyl amide groups could easily be converted, delivering di- and trioxazoles with interesting optical properties. Furthermore, the scope of the gold(I)-catalyzed alkylidene synthesis was investigated. Further functionalizations of these isolable intermediates of the oxazole synthesis were developed and chelate ligands can be obtained. The use of Barluenga's reagent offers a new and mild access to the synthetically valuable iodoalkylideneoxazoles from propargylic amides, this reagent being superior to other sources of halogens.
Base-Promoted Cycloisomerization for the Synthesis of Oxazoles and Imidazoles
Zhang, Lidan,Xiao, Ke,Qiao, Yan,Li, Xin,Song, Chuanjun,Chang, Junbiao
, p. 6913 - 6918 (2018/12/05)
Treatment of propargylamides or propargylamidines with cesium carbonate in DMSO results in the formation of the corresponding oxazoles or imidazoles in good yields. A large variety of substrates with various functional groups are tolerated. DFT study on a model substrate reveals that the reactions proceed via a sequence involving allene formation, intramolecular cyclization, and double-bond isomerization.
