Novel and Mild Route to Phthalocyanines and 3‐Iminoisoindolin‐1‐ones via N , N ‐Diethylhydroxylamine‐Promoted Conversion of Phthalonitriles and a Dramatic Solvent‐Dependence of the Reaction

Refluxing a mixture of phthalonitrile C 6 R 1 R 2 R 3 R 4 (CN) 2 1 (R 1 –R 4 =H), or its substituted derivatives 2 (R 1 , R 3 , R 4 =H, R 2 =Me), or 3 (R 1 , R 4 =H, R 2 , R 3 =Cl) (1 equiv.) and N , N ‐diethylhydroxylamine, Et 2 NOH, (4 equivs.) in methanol for 4 h results ( Route A ) in precipitation of the symmetrical ( 6 and 8 ) and an isomeric mixture of unsymmetrical ( 7 ) phthalocyanines, isolated in good (55–65 %) yields. The reaction of phthalonitriles 1 , 2 , or 4 (R 1 , R 3 , R 4 =H, R 2 =NO 2 ) (4 equivs.) with Et 2 NOH (8 equivs.) in the presence of a metal salt MCl 2 (M=Zn, Cd, Co, Ni) (1 equiv.) in n‐ BuOH or without solvent results in the formation of metallated phthalocyanine species ( 9 – 17 ). Upon refluxing in freshly distilled dry chloroform , phthalonitrile 1 or its substituted analogues 2 , 3 or 5 (R 1 –R 4 =F) (1 equiv.) react with N , N ‐diethylhydroxylamine (2 equivs.) affording 3‐iminoisoindolin‐1‐ones 18 – 21 ( Route B ) isolated in good yields (55–80 %). All the prepared compounds were characterized with C, H, and N elemental analyses, ESI‐MS, IR, and compounds 18 – 21 also by 1D ( 1 H, 13 C{ 1 H}), and 2D ( 1 H, 15 N‐HMBC and 1 H, 13 C‐HMQC, 1 H, 13 C‐HMBC) NMR spectroscopy.