Water‐Soluble Phtalocyanines Containing Aza‐Crown Ether Substituents

A straightforward and generalizable synthesis of metal‐free and metal (Ni, Pb, Lu) derivatives of symmetrically tetrasubstituted phthalocyanines derived from 15, 16‐dibromo‐ or ‐dicyano‐2, 3, 6, 7, 8, 9, 11, 12‐octahydro‐5H‐benzo[e][1, 4, 7, 13]tetroxaza‐cyclopentadecine (1) is described. Quaternarization of the N‐acetyl derivatives 7 in a chloroform/dimethyl sulfate mixture gives phthalocyanines 9 soluble in the pH range of 1 – 13. The electronic spectra of the phthalocyanines in buffered solutions (pH 4, 7, and 10) are examined. Furthermore, the electronic spectra of lutetium bis(phthalocyaninate) 9d in water and in DMSO are compared for the first time.