. J. Chem. 65, 1705Chem. 65, (1987.Hydrolysis of 5-neopentoxy-l,3-diiminoisoindoline gave 5-neopentoxy-l H-isoindole-l,3(2H)-dione (4-neopentoxyphthalimide), which, on treatment with Lawesson's reagent, yielded the thiophthalimides, 5-neopentoxy-lH-isoindole-l,3(2H)-dithione, 2,3-dihydro-6-neopentoxy-3-thioxo-1 H-isoindo-l o n e and 2,3-dihydro-5-neopentoxy-3-thioxo-1 H-isoindo-1 -one. Attempted S-alkylations of the thiophthalimides resulted in the formation of P-isoindigos and N-alkylation products. In a new phthalocyanine synthesis crossed condensations of 1,3-diiminoisoindoline with 5-neopentoxy-1 H-isoindole-l,3(2H)-dithione yielded mixtures of phthalocyanines from which 2-neopentoxyphthalocyanine and 2,16-dineopentoxyphthalocyanine could be purified in part from other phthalocyanines. CLIFFORD C. LEZNOFF, SHAFRIRA GREENBERG, BEN KHOUW et A. B. P. LEVER. Can. J. Chem. 65, 1705Chem. 65, (1987. L'hydrolyse de la nkopentoxy-5 diimino-1,3 indoline conduit a la nkopentoxy-5 1H-isoindole (2H)-dione-1,3 (nkopentoxy-4 phtalimide) qui, par traitement avec le rkactif de Lawesson, fournit les thiophtalimides, ntopentoxy-5 lH-isoindole (2H)-dithione-1,3, dihydro-2,3 ntopentoxy-6 thioxo-3 1 H-isoindolone-1 et dihydro-2,3 ntopentoxy-5 thioxo-3 1 H-isoindolone-1 .Des essais de S-alkyler les thiophtalimides ont conduit A la formation de P-isoindigos et de produits de N-alkylation. Dans une nouvelle synthbse de la phtalocyanine, des condensations de la diimino-1,3 isoindoline avec la nkopentoxy-5 lH-isoindole (2H-dithione-1,3 ont conduit a des mClanges de phtalocyanines a partir desquels on a pu purifier en partie la ntopentoxy-2 phtalocyanine et la dintopentoxy-2,16 phtalocyanine.[Traduit par la revue]Although symmetrical tetra (1-3) and octasubstituted (4-6) phthalocyanines are well known, the synthesis of simple mono-(7), disubstituted (8), and other unsymmetrical phthalocyanines (9, 10) remains a difficult problem. A typical symmetrical phthalocyanine synthesis involves the self-condensation of 5-substituted or 4,5-disubstituted-l,3-diiminoisoindolines (4, 11). A simple strategy available to form unsymmetrical phthalocyanines is the mixed condensation of two different 1,3-diiminoisoindolines to obtain the desired mono-, di-, or trisubstituted phthalocyanines. In fact, condensation of 1,3-diiminoisoindoline (1) and 5-neopentoxy-1,3-diiminoisoindoline (2) does give mixtures of unsubstituted, mono-, di-, tri-, and tetraneopentoxyphthalocyanines (3-8) as expected when analyzed by mass spectr~scopy.~ We envisioned that a completely new approach to phthalocyanine synthesis was required. If we could perform a crossed condensation of substrates in which one of the substrates is unable to self-condense and if we could lower the temperature of phthalocyanine formation so that crossed condensation is favoured over self-condensation of the other substrate, then specifically substituted phthalocyanines could be formed as shown in Scheme 1.Although phthalic anhydrides self-condense, probably via phthalimides to form phthalocyanine...