Benzophenanthrothiophenes: Syntheses, Crystal Structures, and Properties

A new
class of polycyclic heteroarenes based on benzo­[3,4]­phenanthro­[1,2-b]­benzo­[3,4]­phenanthro­[2,1-d]­thiophene
(BPBPT) was prepared from polyaryl thiophenes via regioselective
Scholl reactions. The molecular frameworks of these compounds exhibited
twisted bridges and near-cofacial packing motifs with oppositely or
parallel π-stacked structures depending on the substituents
on the periphery. Theoretical calculation of electronic coupling and
charge mobility was carried out on the basis of the single-crystal
structures. Single crystals of selected benzophenanthrothiophenes
were used in p-channel field-effect transistor device
fabrication, from which the highest mobility was measured as 2.03
cm2 V–1 s–1 from Flu-BPBPT.