An efficient catalytic deprotection of thioacetals employing bismuth triflate: synthesis of pyrrolo[2,1-c] [1,4] benzodiazepines

A simple and efficient deprotection of thioacetals has been achieved by employing bismuth triflate. This method has been effectively employed in the preparation of DNA-binding pyrrolo[2,1-c] [1,4]benzodiazepine and its dimers.