| Abstrakt: |
Naphthalenetetracarboxylic diimides (NDIs) are efficient electron acceptors due to their high electron affinity. They are applied in heterogeneous catalysis and organic electronics. In this work, we report, for the first time, the synthesis of N,N′-bis[3-(triethoxysilyl)propyl]-1,4,5,8-naphthalenediimide (NDI-silane) as a molecular crystal obtained from recrystallization in petroleum ether. The compound is stable in air conditions and chloroform solution. Its crystal structure was determined by single-crystal X-ray diffraction. We have characterized the intermolecular dispersive interactions by density functional theory calculations, indicating that the stability of the crystal in air conditions is related to dispersive interactions. Furthermore, we characterize the optical and photoelectrical properties of thin NDI-silane films, demonstrating photoinduced conductivity over a wide range of temperatures (10–300 K). Remarkably, a venture of NDI-based organosilica can be obtained from stable NDI-silane crystals, prominent materials in organoelectronics and photocatalysis. As a proof of concept, we prepare mesoporous organosilicas with 100% NDI-silane using the ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate as a templating and sol–gel catalytic agent. These materials show a well-formed organosilica network, presenting only T3and T2Si species, as probed by solid-state 29Si NMR. As a result, the mesoporous materials are considerably more resistant to thermal degradation than the crystals, being stable up to 450 °C. According to N2adsorption isotherms and transmission electron microscopy images, they demonstrate microporous and mesoporous structures associated with narrow slitlike pores. |
