A novel and highly efficient copper‐catalyzed intramolecular cyclization reaction of 2‐iodoanilines with nitriles for the synthesis of benzimidazoles with l‐proline as the ligand has been developed. A variety of substituted benzimidazole derivatives can be synthesized with high yields using this approach. Copyright © 2014 John Wiley & Sons, Ltd.

Experimental sectionGeneral Methods.All starting materials were purchased from commercial sources and used without further treatment.Melting points were determined on a Thomas Hoover capillary apparatus and were uncorrected.All known compounds are identified by appropriate technique such as 1 H NMR and compared with previously reported data. 1 H NMR (500 MHz) was recorded on a Bruker 500 spectrometer with tetramethylsilane (TMS) as an internal standard. Mass spectra were recorded on an Agilent technologies 6110 quadrupole LC/MS equipped with an electrospray ionization (ESI) probe operating in positive ion mode. Analytical thin layer chromatography (TLC) was performed on precoated silica gel 60 F254 plates. Yields refer to the isolated yields of the products after

No abstract

A simple and efficient catalytic system for the aerobic oxidation of primary amines into corresponding oximes has been developed, with 3‐methyl‐4‐oxa‐5‐azahomoadamantane as catalyst, acetaldoxime as co‐catalyst and water as solvent. This process, which uses oxygen (O2) as an economic and green oxidant and water as a green solvent, tolerates a wide range of substrates, affording the target oximes in moderate to excellent yields. It was found that high selectivity was achieved when 3‐methyl‐4‐oxa‐5‐azahomoadamantane was used, and E‐type oximes were the only detected products. A possible mechanism for this catalytic process is proposed.magnified image

No abstract