Rapid and efficient oxidation of Hantzsch 1,4-dihydropyridines with sodium periodate catalyzed by manganese (III) Schiff base complexes

Nanosized Mn(acac)3 Anchored on Amino Functionalized Silica for the Selective Oxidative Synthesis of 2-arylbenzimidazoles, 2-arylbenzothiazoles and Aerobic Oxidation of Benzoins in Water

“…Among various transition metals, manganese is probably the most versatile in promoting or catalyzing oxidation reactions [59][60][61][62][63][64][65]. Various supported manganese complexes have been prepared and used for various oxidation reactions [66][67][68][69][70][71].…”

Rapid and efficient biomimetic oxidation of 2-imidazolines to their corresponding imidazoles with NaIO4 catalyzed by Mn(salophen)Cl

“…Metal Schiff base complexes (salen and salophen) have been known as efficient catalysts in the oxidation of organic compounds by single oxygen atom donors. Manganese, chromium, nickel and cobalt Schiff base complexes have been used for these transformations [16][17][18][19][20][21][22][23][24][25].…”

A convenient and efficient protocol for oxidative aromatization of Hantzsch 1,4-dihydropyridines using benzyltriphenylphosphonium peroxymonosulfate under almost neutral reaction conditions

“…7 Consequently, this aromatization reaction continues to attract the attention of organic and medicinal chemists for the discovery of a plethora of protocols applicable to a wide range of DHPs. Many of the reported procedures involve the use of ferric or cupric nitrates on a solid support, 8 ceric ammonium nitrate, 9 clay-supported cupric nitrate accompanied by ultrasound promotion, 10 manganese dioxide or DDQ, 11 nitric oxide, 12 bismuth nitrate penahydrate, 13 PCC, 14 tetrakis-(pyridine) cobalt(II) dichromate, 15 nicotinum dichromate, 16 S-nitrosoglutathione, 17 43 and catalytic amount of Pd/C in acetic acid. 44 However, most of the reported oxidation protocols require an extended period of time for completion, utilize strong oxidants in large excess and afford only modest yields of the products, produce by-products which are difficult to remove, and utilize oxidizing reagents and catalysts which are either highly toxic and expensive or present serious disposal problems.…”