Synthesis of optically active camphorsulphonylbenzimidazoles

Abstract

The preparation of optically active camphorsulphonylbenzimidazole {(bf 1)}, a mixture of regioisomeric 5-nitro- $(2A)4 and 6-nitro-$(2B)$ camphorsulphonylbenzimidazoles, 5-nitro-$(3A)$ and 6-nitro-$(3B)$ 2- methy-camphorsulphonylbenzimidazoles is described. In this study the structure of the purified camphorsulphonylbenzimidazoles $1, 2B, 3A$ and $3B$ was confirmed by their mass and 1H NMR spectral analysis. The specific rotation of each pure compound is also reported.