Pyrene-1,5,6,10-tetracarboxyl diimide: a new building block for high-performance electron-transporting polymers

Abstract

Both naphthalene and perylene derivatives bearing six-membered-ring dicarboximide groups are proven valuable modules for preparing organic electron-transporting semiconductors. However, obtaining their analogue with pyrene appeared challenging, as all previous endeavors resulted in 5- instead of 6-membered dicarboximide rings. Here, we report the first successful synthesis of pyrene-1,5,6,10-tetracarboxyl diimide (PyDI), a centro-symmetric structure comprising two 6-membered dicarboximide groups. Moreover, this molecule undergoes regioselective dihalogenation to afford a 3,8-dibromo-substituted derivative, which may conveniently be incorporated into conjugated polymers via cross-coupling with suitable comonomers. Two representative conjugated polymers, PyDI-T and PyDI-TT, are thus prepared, composed of alternating PyDI and thiophene or bithiophene units. OFETs are then fabricated using these polymers under solution-processing conditions. An optimal electron mobility of 0.335 cm² V⁻¹ s⁻¹ is achieved by PyDI-TT, which clearly demonstrates the potential of 1,5,6,10-PyDI as a potent building block for developing new high-performance electronic-transporting materials.