Iron Sulfide Catalyzed Redox/Condensation Cascade Reaction between 2-Amino/Hydroxy Nitrobenzenes and Activated Methyl Groups: A Straightforward Atom Economical Approach to 2-Hetaryl-benzimidazoles and -benzoxazoles

Abstract

Iron sulfide generated in situ from elemental sulfur and iron was found to be highly efficient in catalyzing a redox/condensation cascade reaction between 2-amino/hydroxy nitrobenzenes and activated methyl groups. This method represents a straightforward and highly atom economical approach to 2-hetaryl-benzimidazoles and -benzoxazoles.

Atomic Layer Deposition of Iron Sulfide and Its Application as a Catalyst in the Hydrogenation of Azobenzenes

“…Iron sulfide (FeS x )i sa ni mportant earth-abundant material that has recently received great attention for av ariety of applications,s uch as solar cells, [1] lithium-ion batteries, [2] and as ac atalyst for hydrogen evolution, [3] oxygen reduction, [4] CO 2 reduction, [5] and organic synthesis. [6] Many of these applications are based on the use of nanostructured FeS x as the active material [7] as nanostructured materials usually have afairly large surface area and thus expose alarge number of active sites,which can considerably boost the performance of active materials.T of abricate nanostructured FeS x ,m any synthetic methods,including solution-based methods, [2a,c,3c,d, 4] mechanical ball milling, [2b] gas-phase sulfidation, [8] and chemical vapor deposition, [1c, 9] have been adopted in the past. On the other hand, atomic layer deposition (ALD) has recently gained significant attention as ah ighly useful deposition technique for fabricating nanostructured materials.…”

An organocatalytic route to 2-heteroarylmethylene decorated N-arylpyrroles

“…While attempts to perform an oxidation of the bis(heteroaryl)methylene position with elemental sulfur [28] or SeO 2 failed, the oxidation of this methylene position was regioselectively carried out by treatment of 5a–e with (NH 4 ) 2 Ce(NO 3 ) 6 (CAN), delivering the alcohols 9a–e (Scheme 6). The methylene oxidation was especially efficient with substrates containing mononitrogenated heteroaryl substituents, with yields ranging from 64–87%.…”

Synthesis of 2‐Arylbenzoxazoles by Hetereogeneous γ‐MnO2 Catalyzed Redox Reaction of o‐Nitrophenol with Benzyl Alcohols or Benzyl Amines

“…reported dppf catalysed redox condensation of o‐nitrophenol with benzylic alcohols for the synthesis of 2‐aryl benzoxazole . Nguyen et al reported iron sulphide catalysed redox condensation of o‐substituted nitro benzenes with alkyl or benzyl amines and 2‐or‐4 methyl heteroarenes for benzoxazole or benzimidazole synthesis– Due to the advantages of reusability, handling and separation from the reaction mixture heterogeneous catalysts have been received more attention in recent years. In this context, Au/TiO 2 catalyst reported by Wang et al.…”