Abstract
In this account we summarized our work on the modification and extension of the thiadiazoloquinoxaline
(TQ) as a strong acceptor unit for organic electronics. While also alternating conjugated
copolymers with different donors were published, the focus here is the description
of variation of the acceptor unit leading to many small molecules with different electronic
properties as indicated from their optical absorptions, cyclic voltammetry (CV) data,
density functional theory (DFT), and time-dependent (TD-DFT) calculations. The extension
with ortho-diquinones seemed a promising way to enlarge the TQ molecules and further increase
their electron affinity. At the end it is demonstrated how these units can be merged
with other acceptors like naphthalenediimide (NDI) and be extended in an iterative
way to extremely long condensed pyrene-fused heteroacenes with TQ end groups just
by ring opening of the thiadiazole five-membered ring followed by further condensations
in an iterative way.
1 Introduction
2 The Synthesis of TQ Cores
3 The Extension of TQ
3.1 The Extension at 4,9-Positions
3.2 The Extension at 6,7-Positions
3.3 The Extension on NDI
3.4 The Extension with TQ for Endcapping (Bis TQ)
4 Conclusions
Key words
thiadiazoloquinoxalines - strong acceptor - benzothiadiazoles - nitrogen heterocycles
- polycyclic aromatics
