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• 1125527-00-5 C₂₀H₁₆Cl₂N₄S₂ 
• 934-32-7 1H-benzimidazol-2-amine 
• 63503-60-6 3-chlorophenylboronic acid 
• 1056477-06-5 2-bromocyclohexanone 
• 6145-41-1 3-chlorophenylguanidine 
• 4857-06-1 2-chloro-1H-benzoimidazole 
• 108-42-9 3-chloro-aniline 

Relevant academic research and scientific papers

BENZIMIDAZOLO[1,2-A]BENZIMIDAZOLE DERIVATIVES FOR ORGANIC LIGHT EMITTING DIODES

Compounds of formula (I) and their use in electronic devices, especially electroluminescent devices: (I) wherein at least two of the substituents R1 and R2, R2 and R3, R3 and R4, R5 and R6, R6 and R7, or R7 and R8 form together one of the following ring systems (IIa), (IIb) (IIc). When used as charge transport material, charge blocker material and/or host material in electroluminescent devices, the compounds of formula (I) may provide improved efficiency, stability, manufacturability, or spectral characteristics of electroluminescent devices and reduced driving voltage of electroluminescent devices.

A new NBS/oxone promoted one pot cascade synthesis of 2-aminobenzimidazoles/2-aminobenzoxazoles: A facile approach

A new strategy for the synthesis of 2-aminobenzimidazoles via a reaction of α-halogenated cyclohexanone with guanidine is reported. It provides a facile N-bromosuccinimide (NBS) mediated transition metal free, sustainable path for the synthesis of 2-substituted azoles. NBS along with the oxone promotes in situ halogenation of cyclohexanone, which in turn, when allowed to react with guanidine, afforded 2-aminobenzimidazoles (2-ABI). This eco-friendly protocol provides a competent laboratory synthesis method associated with significant advantages such as greater selectivity, cost-efficiency, mild reaction conditions, absence of chromatographic purification, clean reaction profile, and a simple work-up procedure to furnish high yields. The structures of all the synthesized compounds were confirmed on the basis of IR, 1H and 13C NMR, mass spectrometry, and elemental analyses data. In addition, we have also extended the scope of this strategy for obtaining 2-amino substituted benzoxazoles.

Copper-Catalyzed C NH2Arylation of 2-Aminobenzimidazoles and Related C-Amino-NH-azoles

A copper(II)-catalyzed selective C NH2arylation of 2-aminobenzimidazoles and related C-amino-NH-azoles was achieved in presence of 2,2′-bipyridine and cesium carbonate at 60 °C under open air conditions and this is first method for the copper-catalyzed selective C NH2arylation in the presence of other reactive nucleophilic sites. Previously unexplored heteroaromatics possessing multiple nucleophilic sites that are selectively arylated at the C NH2position are obtained, providing an exceptional tool for rapid delivery of a diverse array of medicinally important C NH(aryl) derivatives of aminoazoles without any protection/deprotection of ring N H bonds. It is first example for the selective C NH2arylation of 5-aminoindazole, 4-aminopyrazole, 5-aminopyrazole, 9H-purine-6-amine, and 1H-pyrazolo[3,4-d]pyrimidin-4-amine derivatives. (Figure presented.) .

One-pot synthesis of five and six membered N, O, S-heterocycles using a ditribromide reagent

In a one-pot procedure, bromine less brominating reagent 1,1′-(ethane-1,2-diyl)dipyridinium bistribromide (EDPBT) has been utilized as an efficient desulfurizing agent for the construction of a library of heterocycles containing N, O, and S starting from aryl/alkyl isothiocyanates. In this approach, aryl/alkyl isothiocyanate reacts with o-phenylenediamine (o-PD), o-aminophenol, and o-aminothiophenol to form their monothiourea which on desulfurization with EDPBT led to the formation of corresponding 2-aminobenzimidazoles, 2-aminobenzoxazoles, and 2-aminobenzothiazoles, respectively. An interesting regioselectivity was observed for unsymmetrical thiourea having a naphthyl moiety on the one side and an ortho amino or an ortho hydroxy phenyl group on the other side giving a completely different product which is mainly dependent on the nature of the nucleophiles (-OH or -NH 2). Further, the bis-thioureas resulted from the aliphatic 1,2-diamine with 2 equiv of aryl isothiocyanates on treatment with EDPBT gave imidazolidenecarbothioamides, whereas bis-thioureas resulted from aromatic 1,2-diamine yielded benzimidazoles with concurrent expulsion of an isothiocyanate unit. This method is simple and applied to various substrates which are amenable to bromination that reveals the desulfurizing ability of EDPBT predominating over its brominating ability. Finally, the spent reagent EDPDB can be recovered, regenerated, and reused without any loss of activity.

Desulfurization mediated by hypervalent iodine(III): A novel strategy for the construction of heterocycles

The desulfurization ability of diacetoxyiodobenzene (DIB) has been explored in the preparation of isothiocyanates from the corresponding dithiocarbamate salts. The in situ generated isothiocyanates reacted with o-phenylenediamine and o-aminophenol to form monothioureas, which, on treatment with a further equivalent of DIB in one pot, gave benzimidazoles and aminobenzoxazoles, respectively. Aliphatic 1,2-diamines on reaction with 2 equiv. of isothiocyanate followed by treatment with DIB gave imidazolidenecarbothioamides, whereas the treatment of aromatic 1,2-diaminebis(thioureas) yielded benzimidazoles with the concurrent formation of isothiocyanate. The driving force for the formation of the latter is the aromatization of the product. The use of DIB makes these methods simpler and more efficient, giving high yields of the desired products in one pot. Wiley-VCH Verlag GmbH & Co. KGaA, 2008.