Kommi, Damodara N. published the artcile“All-water” one-pot diverse synthesis of 1,2-disubstituted benzimidazoles: hydrogen bond driven synergistic electrophile-nucleophile dual activation’ by water, Category: imidazoles-derivatives, the publication is Green Chemistry (2013), 15(3), 798-810, database is CAplus.
A new “all-water” tandem arylaminoarylation/arylaminoalkylation-reduction-cyclization route is reported for one-pot diversity oriented synthesis of regiodefined 1,2-disubstituted benzimidazoles. Water plays a crucial and indispensable role through hydrogen bond driven synergistic electrophile-nucleophile dual activation’ in the formation of N-mono-aryl/aryl alkyl/alkyl/cycloalkyl o-nitroanilines under metal and base-free conditions to replace the transition metal-based C-N bond formation (aryl amination) chem. and underlines the origin of regiodefined installation of the diverse selection of aryl, aryl alkyl, and alkyl/cycloalkyl groups as substituents on the benzimidazole scaffold to form the 1,2-disubstituted benzimidazoles. The influence of the hydrogen bond effect of water in promoting the arylaminoarylation reaction under base and metal-free conditions has been realized through observation of inferior yields in D2O compared to that obtained in water during the reaction of o-fluoronitrobenzene with aniline sep. performed in water and D2O under similar exptl. conditions. Water also provides assistance in promoting the subsequent nitro reduction and in the final cyclocondensation steps. The role of water in promoting the cyclocondensation reaction through hydrogen bonds is realized by the differential product yields during the reaction of mono-N-phenyl-o-phenylenediamine with benzaldehyde performed sep. in water and D2O. The better hydrogen bond donor and hydrogen bond acceptor abilities of water compared to those of the organic solvents are the contributing/deciding factors for making the new water-assisted tandem arylaminoarylation/arylaminoalkylation-reduction-cyclization strategy for the diversified synthesis of the regiodefined 1,2-disubstituted benzimidazoles effective in an aqueous medium, making it represent a true “all-water chem.”.
Green Chemistry published new progress about 2622-67-5. 2622-67-5 belongs to imidazoles-derivatives, auxiliary class Benzimidazole,Benzene,Benzimidazole, name is 1,2-Diphenyl-1H-benzo[d]imidazole, and the molecular formula is C19H14N2, Category: imidazoles-derivatives.
Referemce:
https://en.wikipedia.org/wiki/Imidazole,
Imidazole | C3H4N2 – PubChem