Synthesis of Phthalocyanines Using Triorganoindium Reagents

Phthalocyanines (Pcs) have attracted much attention due to their singular electronic properties, exceptional chemical and photochemical stabilities, and strong absorption of visible light [1]. Although there is a great variety of methods for the preparation of substituted phthalocyanines, introducing the substituents either on the phthalonitrile precursor or on the already formed phthalocyanine core, we have decided to explore the palladium-catalysed coupling reaction between haloaromatics and triorganoindium reagents [2]. The latter benefits from high reactivity, efficiency, versatility and chemoselectivity, together with the low toxicity associated with indium derivatives. We have indeed already experimented with this process, first exploring some basics about the scope [3] and new procedures for the synthesis of the triorganoindium reagents [4], and later using it in the preparation of hole transporting materials [5]. In this occasion we will discuss our more recent results in the preparation of substituted phthalocyanines using triorganoindium reagents.

Taking advantage of the previously commented properties of Pcs, the synthesized compounds are excellent candidates for the preparation of photovoltaic devices, either Dye-Sensitized Solar Cells (DSSCs) or Bulk Heterojunction (BHJs) [6,7].

 Acknowledgements. This work has been supported by the Spanish Ministerio de Economía y Competitividad, Generalitat Valenciana and the European FEDER funds (grants CTQ 2010-20349, CTQ2011-26455, CTQ2013-47922-R, PROMETEO 2012/010 and ISIC/2012/008).

 References

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