Two-step synthesis of new fused systems based on [1,2,5]oxadiazolo[3,4-b]quinoxaline by a combination of the Scholl reaction and nucleophilic aromatic substitution of hydrogen (SNH)

A simple synthetic route to poorly available polycyclic systems with a [1,2,5]oxadiazolo-[3,4-b]quinoxaline backbone has been developed, which is based on the sequence of nucleophilic aromatic substitution of hydrogen and the Scholl cross-coupling. According to the data from electrochemical and photophysical measurements, the synthesized compounds can be potentially considered as the narrow-gap (from 1.97 to 2.34 eV) n-type organic semiconductors, the energy levels of which are comparable to those of top commercially available electronic semiconductors.