Binuclear phthalocyanines covalently linked through two- and four-atom bridges

Binuclear phthalocyanines in which the two phthalocyanine nuclei are covalently linked through four-atom bridges, derived from catechol, have been prepared and characterized. Metal-free 2,9,16,23-tetra-(3,3-dimethylbutyl)phthalocyanine and 2,9,16,23-tetra-(2-trimethylsilylethyl)phthalocyanine were prepared as examples of non-oxygenated mononuclear phthalocyanines soluble in organic solvents. Catalytic hydrogénation of 1,2-bis-(3,4-dicyanophenyl)ethyne and 1,4-bis-(3,4-dicyanophenyl)buta-1,3-diyne gave 1,2-bis-(3,4-dicyanophenyl)ethane and 1,4-bis-(3,4-dicyanophenyl)butane respectively. From these precursors, metal-free phthalocyanine dimers containing ethylene and tetramethylene bridges, joining the phthalocyanine nuclei, were prepared. Two of the two-atom bridge phthalocyanine dimers represent the first characterized phthalocyanine dimers not containing alkoxy or oxygenated groups.