Abstract
A general synthesis of unsymmetrically substituted dienophilic nickel phthalocyanines is described. The desired nickel phthalocyanine complexes [3,4,10,11,17,18-hexakis(2-ethyl-hexyloxy)tribenzo(b,g,i]-24,27-di-hydro-24,27-epoxynaphthalo[q]porphyrazinato]nickel(II) (4) and dodeca alkoxy-substituted PcNi (5) were synthesized using a statistical approach by the condensation of 1,2-dicyano-4,5-bis(2-ethylhexyloxy)benzene (1) or 1,2-dicyano-3,4,5,6-tetrakis(2-ethylhexyloxy)benzene (2) and 6,7-dicyano-1,4-dihydro-1,4-epoxy-1,4-dimethylnaphthalene (3) in the presence of nickel(II) acetate. Reaction of 4 or 5 with tetraphenyl-cyclopentadieneone (9) lead to the phthalocyanine-tetracyclone adducts 10 and 11, respectively, which are precursors for intermediate adducts 12 and 13 containing isobenzofuran moiety as diene subunits. The dimer 14 was synthesized from 4 and the isobenzofuran intermediate 12. Dehydrogenation of the Diels-Alder product 14 to the fully conjugated derivative 15 was carried out successfully with p-toluenesulfonic acid.
A class of unsymmetrically substituted dienophilic nickel phthalocyanines derivatives has been synthesized and characterized and were used for the synthesis of the fully aromatized bridged bimolecular phthalocyanine.