Synthesis of 1,2-disubstituted benzimidazoles, 2-substituted benzimidazoles and 2-substituted benzothiazoles in SDS micelles

An Inorganic Iodine‐Catalyzed Oxidative System for the Synthesis of Benzimidazoles Using Hydrogen Peroxide under Ambient Conditions

“…Notably, together with the good results with benzylic, allylic, and heteroaryl aldehydes, the yields obtained from the reaction of aliphatic aldehydes under the same conditions are also high (entries 12-13). In view of the fact that the reaction of aliphatic aldehyde is much more difficult than the reaction of benzylic aldehyde, [26] the results obtained with the present procedure are very satisfactory. Next, we extended this synthetic method for the preparation of bis-benzimidazoles in a 2:1 molar ratio of phenylenediamine/terephthaldicarboxaldehyde (entry 16).…”

“…Various oxidative reagents, such as MnO 2 , [15] Pb(OAc) 4 , [16] PhI(OAc) 2 , [17] Oxone, [18] DDQ, [19] I 2 , [20] 1,4-benzo-quinone, [21] tetracyanoethylene, [22] benzofuroxan, [23] NaHSO 3 , [24] Na 2 S 2 O 5 , [25] (NH 4 ) 2 S 2 O 8 , [26] and nitrobenzene or DMF (high-boiling oxidant/solvent) [27] have been employed to effect the dehydrogenation step. Although many of these methods are practical, some have problems such as the use of dangerous or toxic reagents, or the formation of N-benzylbenzimidazole side products resulting from further reaction of the aldehyde with benzimidazoline prior to oxidation.…”

Synthesis of novel 4-(1H-benzimidazol-2-yl)benzene-1,3-diols and their cytotoxic activity against human cancer cell lines

“…Benzimidazole-4,7-diones show cytotoxicity against colon, breast and lung cancer cell lines (Gellis et al, 2008). The broad profile of therapeutic applications of compounds with a benzimidazole core and their valuable biological properties has prompted extensive studies of their synthesis (Perry and Wilson, 1993;Brain and Brunton, 2002;Yang et al, 2005;Zhang et al, 2009;Bahrami et al, 2010;Peng et al, 2010).…”

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

“…Very few catalytic systems have been reported for the synthesis of 2-arylbenzimidazoles in water. For example, Bahrami et al [78] used H 2 O 2 /HCl in water at 80°C and more recently, using SDS micelles at 25°C [79]; Mukhopadhyay et al [80] have used boric acid and glycerol at 80°C. However, our catalytic system is successful at 70°C with similar or higher yields and moreover, recyclable under the reaction conditions.…”