Palladium-Catalyzed Decarboxylative Cross-Coupling of 1,3,4-Oxadiazoles with Alkynoic Acids: A Simple Route for the Preparation of 2-Alkynylated 1,3,4-Oxadiazoles
作者:Ch. Reddy、L. Reddy、P. Reddy
DOI:10.1055/s-0036-1588115
日期:——
4-oxadiazole derivatives have been synthesized by the decarboxylative cross-coupling of alk-2-ynoic acids with 2-(het)aryl-1,3,4-oxadiazoles, employing palladium(II) chloride as the catalyst and silver(I) oxide as an oxidant with 1,3-bis(diphenylphosphanyl)propane as a ligand. Products were formed in high yields with no byproduct. For the first time 2-alk-1-ynyl-5-(het)aryl-1,3,4-oxadiazole derivatives have
The simplest coupling: Copper‐mediated direct oxidative cross‐coupling of 1,3,4‐oxadiazoles and oxazoles with terminal alkynes proceeds through cleavage of sp2 CH and sp CH bonds to furnish the corresponding alkynylazoles in good yields. The reaction is tolerant toward various substitution patterns of substrates and allows the facile construction of azole‐core π‐conjugated systems.