Optically active ‘adjacent’ type non-centrosymmetrically substituted phthalocyanines

Abstract

Optically active ‘adjacent’ type non-centrosymmetrically substituted phthalocyanines (Pcs) and benzo-substituted Pcs having π-systems with C_2v symmetry have been synthesized in high yields in a mixed condensation using bisphthalonitriles (which do not racemize under general Pc formation conditions) and a second phthalonitrile, and characterized by UV–VIS, natural and magnetic circular dichroism spectroscopy.

References

1. Reaction was carried out at room temperature for three days (C. C. Leznoff, S. M. Marcuccio, S. Greenberg and A. B. P. Lever, Can. J. Chem., 1985, 63, 623).
2. All compounds gave satisfactory elemental analytical data. Selected data for1: Off-white needle [silica, benzene–EtOAc (2∶1 v/v), R_f 0.58], recrystallized from MeCN–Et₂O, mp 230–231 °C; yield: 95.2 and 90.4% for (S)-1 and (R)-1, respectively. [α]_D–29.2 and 29.6 for (S)-1 and (R)-1, respectively (c 1, CH₂Cl₂); δ(60 MHz, CDCl₃) 7.7–8.1 (m, 4 H), 7.0–7.6 (m, 14 H); m/z(EI) 538 (100%, [M⁺]); For H₂2:δ_H(500 MHz, CD₂Cl₂) 6.0–9.2 (m, 36 H, arom), –4.54 (s, 2 H, pyrrole); m/z(FAB) 1078.3 (100%, [M⁺]); a yield by direct methods was 35.7% for (S)-H₂2, recrystallized from CH₂Cl₂–MeOH. For Co2: m/z(FAB) 1135 (54%, [M⁺]), 533 (41), 459 (100). For H₂3: m/z(FAB) 916 (100%, [M⁺]). For Zn3: δ_H(500 MHz, CD₂Cl₂) 6.5–8.7 (m, 22 H, arom), 4.15 (br s, 12 H, OCH₃). For (S)-H₂4: δ(500 MHz, CD₂Cl₂) 6–9 (m, 28 H, arom), 1.3–1.8 (m, 18 H, CH₃), –2.40 (br s, H, pyrrole H at naphthalene site), –4.05 (br s, H, pyrrole H at benzene site). Since, as shown in Fig. 1, UV–VIS absorption, MCD and especially CD spectra change depending on the solvent the details of these spectra will be reported in a full paper.
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