Construction of Polyaromatic Hydrocarbons Containing Sulfur and Nitrogen via Controllable Domino Reactions and DFT Studies

Polyaromatic
hydrocarbons (PHAs) containing heteroatoms have attracted
considerable attention due to their potential utility in electronic
devices. This work reported a novel domino reaction between an aryne
precursor and azadiene bearing a benzothiophene moiety to produce
a series of PHAs containing sulfur and nitrogen atoms. Further transformation
of the product enabled concise synthesis of a new AIEgen, whose photophysical
properties were characterized. Density functional calculations on
the reaction mechanism revealed that the in situ generated
aryne could trigger either a [4 + 2] or [3 + 2] process with azadiene,
in which the regioselectivity was mainly a result of the heteroatom
effect and may be understood by means of Houk’s distortion-interaction
model.