Efficient diborane-mediated synthesis of phthalocyanines carrying amino 3 groups near the macrocycle

GABRIELA A. GAUNA A, DIEGO COBICE, JOSEFINA AWRUCH

POLYHEDRON

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2012 vol. 46 p. 90 - 94

0277-5387

N-(3,4-dicyanophenyl)piperidine-2,6-dione (2) and 4-phthalimidoph-thalonitrile (3) were synthesized in 24% and 74% yield respectively, using 4-aminophthalonitrile as the starting material. Treatment of 2 and 3 with zinc acetate in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene gave respectively phthalocya- nines 4 and 5, whose reduction with diborane afforded dyes 6 and 7. Quaternization of 6 and 7 with iodo- methane gave cationic zinc(II) phthalocyanines 8 and 9 respectively. A bathochromic shift was observed in the absorption spectra when amino and ammonium groups were present near the macrocycle in com- parison with those dyes carrying alkylamino and quaternary alkyl ammonium salts as peripheral substituents.