Electrochemical Desulfurative Cyclization Accessing Oxazol-2-amine Derivatives via Intermolecular C–N/C–O Bond Formation

Access to 3-Amino-[1,2,4]-triazolo Pyridines and Related Heterocycles via Electrochemically Induced Desulfurative Cyclization

“…On the basis of the experimental results (see SI for details) and previous reports, a plausible mechanism is illustrated (Scheme ). First, the nucleophilic addition of 2-hydrazino­pyridine ( 1a ) to phenyl isothio­cyanate ( 2a ) generates thio­semicarbazide ( A ), which further undergoes deprotonation in the presence of a base to form an intermediate C .…”

“…Electrochemical approaches may be applied for the synthesis of heterocycles via the formation of intermolecular or intramolecular C–N bonds with traceless electrons as redox agents . Notably, one-pot preparation of oxazol-2-amine derivatives has been achieved in our group, where iodine molecules were generated in the anode cycle to promote the process of desulfurative cyclization.…”

Electrochemical Multicomponent Cascade Radical Process Enabling Synthesis of Iodomethyl Spiropyrrolidinyl‐Oxindoles

“…Based on the above experimental results and previous reports, [ 15‐18 ] a tentative mechanism for the generation of the spiropyrrolidinyl‐oxindoles via the electrochemical reaction of indole derivatives was proposed in Scheme 4. As iodine ions (I − ) shows a lower oxidative potential than CF 3 SO 2 Na, [ 19 ] the reaction starts from the anodic oxidation of iodine ions to generate iodine molecule, which oxidizes CF 3 SO 2 Na to generate CF 3 (O)SO· radical. Under the described conditions, the formation of the product coming from the addition of the trifluoromethyl in situ generated from CF 3 SO 2 Na is not observed.…”

Photochemical three-component assembly of tri-substituted oxazoles through a carbenic phosphorus-nitrile hybrid ylide formation/trapping cascade

“… 3 In the past few decades, several catalytic and other methods for the synthesis of oxazole derivatives have been well documented, such as intramolecular 4 or intermolecular 5 cyclization of acyclic precursors, metal-catalyzed coupling of functionalized oxazoles with suitable reagents, 6 and oxidations of oxazolines, 7 or other relevant protocols. 8 Despite significant advances, most methods face the limitation of inaccessible starting materials and the utilization of transition-metal catalysts or additional oxidants. Moreover, reports on the direct approach to fully functionalized oxazoles are scarce.…”