Regioselective synthesis of oxazole derivatives via palladium-catalyzed and copper-mediated cascade oxidative cyclization

Abstract

A novel Pd-catalyzed/Cu-mediated oxidative cyclization has been developed for the synthesis of trisubstituted oxazoles, which is thought to proceed through cascade formation of C-N and C-O bonds. In this protocol, four hydrogen atoms were removed and water was used as the oxygen atom source.

Iodine Mediated One‐Pot Synthesis of Polyarylated‐Oxazoles from Internal Alkynes

“…Recent time, researchers devoted themselves for development of oxazole derivatives from internal alkynes using different iodine reagents as well as iodine itself, [9b–e] sometimes including metal salts [9f–g] . Moreover, oxazole derivatives were synthesized from methyl ketones, internal alkenes, amino acid and 1,3‐dicarbonyl compound using iodine reagents and molecular iodine [9h–m] .…”

Chemoselective Intramolecular Wittig Reactions for the Synthesis of Oxazoles and Benzofurans

“…One of the methods available for the synthesis of this five-membered heteroaromatic ring is direct oxidation of oxazolines . Alternative routes to oxazole synthesis rely on the transition metal- or organocatalyst-mediated cyclization of acyclic precursors, functionalization of oxazoles, and others …”

BF3·OEt2-TFAA Mediated Tetra-Functionalization of Amino Acids - Synthesis of Di- and Tri-Substituted 2-Trifluoromethyl Oxazoles in One Pot

“…The most used approach is cyclization involving α-acylaminoketone/α-acyloxyketone/α-haloketone, primary amide/alkyne and nitrile/amine, and α,β -unsaturated carbonyls. The next one is regioselective functionalization of the oxazole core through metalations and subsequent functionalization . The third and least explored category is the multicomponent reactions, which are highly efficient and atom economical .…”