Synthesis of Germoxysilicon Phthalocyanines

Phthalocyanines, aromatic, macrocyclic compounds with a wide range of industrial applications, are heavily conjugated ring systems which can chelate metals or metalloids. This chelated center can then act as an attachment site for functionalization or oligomerization. Prior characterization of one such group of siloxysilicon dimeric phthalocyanine crystals via X-ray crystallography found a series of unexpected torsional angles, hypothesized to indicate the presence of a previously unexplored intramolecular interaction. To further explore this phenomenon, a series of synthetic routes for novel dimeric silicon phthalocyanine crystals suitable for X-ray crystallography were investigated. Following unsuccessful attempts to synthesize precursor bis-hydroxy dimeric silicon phthalocyanine, a novel triethyl-germoxy-functionalized silicon phthalocyanine was proposed to explore the impact of solubility and functional group bond strength on dimerization. A novel germoxy-functionalized silicon phthalocyanine product was synthesized, with preliminary characterization revealing the presence of both monomeric and dimeric species suitable for separation, crystallization, and structural analysis. Further investigation into this class of silicon phthalocyanines will generate a parallel set of structural data to those previously documented for analysis of torsional angles and may contribute to a deeper understanding and development of the oligomerization of silicon-chelated phthalocyanines.