A general method for the preparation of N-heterocyclic carbene-silver(I) complexes in water

A new synthetic method leading to N-heterocyclic carbene-silver(I) complexes [(R-2-NHC)(2)Ag](+) [AgX2](-) is developed by using benzimidazolium compounds, NaOH (as a base), silver salts and water (as the reaction medium). Single-crystal X-ray structure revealed that compound 1 comprises a linear [Ag-(Et-2-Bimy)(2)](+) cation and a linear [AgBr2](-) anion. These two ions are linked through an Ag-I-Ag-I association and staggered at an angle of 90.3A degrees.