Synthesis of 4-[(1<i>H</i>-Benzimidazol-2-yl)sulfanyl]benzaldehyde and 2-({4-[(1<i>H</i>-Benzimidazol-2-yl)sulfanyl]phenyl}methylidene)hydrazine-1-carbothioamide

Abstract

Here we describe the preparation of 2-(4-((1H-benzo[d]imidazol-2-yl)thio)-benzylidene)-hydrazine-1-carbothioamide in two steps. In the first step, 1,3-dihydro-2H-1,3-benzimidazole-2-thione was reacted with 4-fluorobenzaldehyde in DMSO to get 4-[(1H-benzimidazol-2-yl)sulfanyl]benzaldehyde in high yield. The reaction of the obtained aldehyde with thiosemicarbazide in ethanol at reflux temperature yielded 2-({4-[(1H-benzimidazol-2-yl)sulfanyl]phenyl}methylidene)hydrazine-1-carbothioamide. The structure of the synthesized compounds was established by NMR spectroscopy (1H, 13C), mass spectrometry, and infrared spectroscopy.

Keywords

• benzimidazole
• nucleophilic aromatic substitution
• thiosemicarbazone