Isolation and structural characterization of 1,5-benzodiazepinium cation in an inorganic-organic hybrid compound [C12H17N2]3[Bi2Cl9]·2EtOH

The compound [C12H17N2]3[Bi2Cl9]·2EtOH (1), that has been synthesized from bismuth trichloride and o-phenylenediamine (opda) in ethanol at an aerial ambient condition, illustrates the conversion of opda to 2,3-dihydro-1H-1,5-benzodiazepinium cation through its reaction with acetone that is formed in situ from aerial ethanol oxidation. The supramolecular hydrogen bonding interactions between [Bi2Cl9]3− and [C12H17N2]+ in the crystal structure of 1 play an important role in the stabilization of cationic form of 2,3-dihydro-1H-1,5-benzodiazepine and in obtaining emission signals of the organic moiety, which is otherwise not emissive. Compound [C12H17N2]3[Bi2Cl9]·2(2-PrOH) (2), that has been isolated from 2-propanol (instead of ethanol), is isostructural with compound 1.