Process for the preparation of optically active derivatives of 2-(2-pyridylmethylsulfinyl)-benzimidazole via inclusion complex with 1,1'-binaphthalene-2,2′diol

Abstract

Process for the preparation of optically active derivatives of 2-(2-piridylmethylsulfinyl)-benzimidazole, or salts thereof, by resolution of the corresponding racemic derivatives of 2-(2-piridylmethylsulfinyl)-benzimidazole. The resolution is performed through the formation of inclusion complexes with (S)-(−) or (R)-(+)-[1,1'-Binaphthalene]-2,2′-diol in the presence of an amine, followed by the break of the inclusion complex by treatment with an hydroxide of an alkaline metal. The enantiomer of the derivative of 2-(2-piridylmethylsulfinyl)-benzimidazole may be obtained by extractions at a particular pH with a suitable organic solvent. The process allows to perform the resolution with high yields and high optical purity, without using neither toxic solvents nor chromatography.