Subphthalocyanines: Supramolecular Organization and Self-Assembling Properties

Subphthalocyanines (SubPcs), phthalocyanine analogues, are intriguing compounds made of three diiminoisoindoline units N-fused around a boron atom. Their 14 pi-electron aromatic core associated with their curved structures render them appealing building blocks for the construction of multicomponent photo- or electroactive assemblies. Recently, the development of an improved synthetic methodology for axially substituted SubPc allowed the efficient synthesis of a variety of SubPc-based hybrids.

 To enhance the understanding of the nature of these curve pi-extended surfaces, we have undertaken a series of studies, including the synthesis and characterization of subphthalocyanine-based capsules. These supramolecular systems have been successfully been employed for the encapsulation of fullerenes. Furthermore, it was possible to evaluate the binding constants of the host-guest complexes. Finally, a full study of the photophysical properties revealed that the subphthalocyanines can undergo an energy transfer transduction of singlet excited state energy to the fullerene inside the cavity upon photoexcitation.

 SubPc pi-systems can be organized at supramolecular level. Thus, the self-assembly of axial dipolar subphthalocyanine molecules in the presence of electric fields leads to uniaxially oriented columnar liquid crystalline materials that exhibit permanent polarization.

 References

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