Microwave-Assisted Base-Catalyzed Cyclization and Nucleophilic Substitution ofO-Azidobenzanilides to Synthesize 1,2-Disubstituted Indazol-3-ones

Electrochemical synthesis of N,N′-disubstituted indazolin-3-ones via an intramolecular anodic dehydrogenative N–N coupling reaction

“…Conventionally, indazolin-3-ones can be synthesized by N-C bond formation, starting from hydrazino aryl compounds, [11][12][13][14][15][16][17] via N-N bond formation, starting from o-azidobenzamides, 18 or by oxidative or reductive intramolecular N-N bond formation in o-aminobenzamides [19][20][21][22] or o-nitrobenzamides, [23][24][25] respectively. However, these methods involve harsh reaction conditions, such as high temperatures, strong bases or acids and the use of highly toxic and carcinogenic hydrazine or azide precursors containing leaving groups.…”

“…However, these methods involve harsh reaction conditions, such as high temperatures, strong bases or acids and the use of highly toxic and carcinogenic hydrazine or azide precursors containing leaving groups. [11][12][13][14][15][16][17][18] Further, dangerous oxidizing and reducing agents in stoichiometric amounts or transition metal catalysts are necessary. [19][20][21][22][23][24][25][26] This leads to a high amount of reagent waste, a poor atom economy and safety hazards.…”

Synthesis and Anti-Inflammatory Activity of N(2)-Arylindazol-3(2H)-One Derivatives: Copper-Promoted Direct N-Arylation via Chan–Evans–Lam Coupling

“…HRMS (EI) calcd for C 20 H 15 N 3 O 3 (M) + 345.1113, found 345.1110. [CAS RN: 1182783-81-8] [ 29 ].…”

A B2(OH)4-Mediated Synthesis of 2-Substituted Indazolone and Its Application in a DNA-Encoded Library

“…Due to their versatility in pharmaceutical applications, many synthetic attempts to construct indazolone cores have been made (Figure ). , These methods are complementary, providing avenues to access various substitution patterns. However, these methods still have some potential limitations at some levels.…”