Synthesis and spectral properties of 1,2,5-thiadiazolo-, 1,2,5-selenadiazolo-, and benzo-fused β-phenyl-substituted porphyrazines

Abstract

Cross cyclotetramerization of trans-2,3-diphenylbutanedinitrile with 1,2,5-thia(selena)diazole-3,4-dicarbonitriles or phthalodinitrile in the presence of magnesium butoxide gave mixtures of Mg(II) porphyrazine complexes which were treated with trifluoroacetic acid to isolate unsymmetrical hexaphenyl-substituted 1,2,5-thia(selena)diazolo-and benzo-fused porphyrazines together with diphenyltribenzoporphyrazine. Their 1H NMR and electronic absorption spectra (in the UV and visible regions) were recorded. The effect of benzene and heteroring fusion on the electronic and steric structure and spectral properties of porphyrazine derivatives was studied in terms of the molecular orbital perturbation theory and semiempirical quantum-chemical calculations (AM1, PM3, ZINDO/S, CNDO/S)

Porphyrazines with Annulated Chalco¬gen-Containing Heterocycle: Study of Spectral-Luminescent Properties and Quantum-Chemical Calculations of the Excited Electronic States

“…The results of spectral luminescence study obtained for Н 2 {SN 2 }-PAPh 6 and Н 2 {SеN 2 }PAPh 6 are compared with the data on octaphenylporphyrazine (H 2 PAPh 8 ), and results for H 2 {SeN 2 }PA(Bz t Bu) 3 -with the data for the corresponding phthalocyanine, H 2 PA(Bz t Bu) 4 6 and Н 2 {SеN 2 }PAPh 6 was conducted as described earlier. [1] During chromatographic isolation of these compounds the symmetrical porphyrazine H 2 PAPh 8 was obtained as by-product. Its spectral properties are identical with the product obtained following the original Linstead procedure.…”

Conversion of 1,2,5-Selenadiazoloporphyrazine to Diformamidoporphyrazine

“…However, in the UV-vis spectrum of the reaction mixture no indication can be seen about presence of [H 2 {SN 2 }PAPh 6 ] which have Q-bands at 574 and 679 nm. [13] [7] we can conclude that also in the case of the free base [H 2 {SeN 2 }PAPh 6 ] the reaction mixture after treatment with H 2 S contains along with diaminoporphyrazine [H 2 PA{NH 2 } 2 Ph 6 ] ( 2 ) some amount of its precursors with the S,Se-substituted diazine and diazepine rings [H 2 {(NH) 2 Х)}PAPh 6 ] (X = SSe, S 2 , S 3 ). One can suppose that upon evaporation of the solvent before and/or during mass-spectral measurements these species are transformed to the more stable 1,2,5-thiadiazole derivative [H 2 {SN 2 }PAPh 6 ].…”

“…This is in contrast with successful use of this procedure for preparation of Mg II complexes of 1,2,5-thiadiazolo-, 1,2,5-selenadiazolo-and benzoannulated b-phenylsubstituted porphyrazines from diphenylfumarodinitrile and corresponding heterocyclic dinitrile or phthalodinitrile. [7,13] For peripheral modification ( ii) we have chosen [H 2 {SeN 2 }PAPh 6 ] (1) and studied first its behaviour in the presence of H 2 S. Bubbling of H 2 S into the solution of [H 2 {SeN 2 }PAPh 6 ] (1) in pure chloroform did not produce any changes in the UV-vis spectra. However, in the presence of pyridine additions (10-20%) the colour of the solution saturated with H 2 S was rapidly changed from green to dark blue.…”

“…7,8,12,13,17,18-Hexaphenyl[1,2,5]selenadiazolo [3,4-b]porphyrazine, [H 2 {SeN 2 }PAPh 6 ] (1) was prepared as described in our recent works. [7,13] 2, 8,12,13,17, …”

Behaviour of Low-Symmetry Crown-Phthalocyanine in Solution: Concentration Aggregation vs. Cation-Induced Assembly

“…[15] In the case when reactivity of starting nitriles is different, distribution of reaction products can significantly deviate from binomial. [16] Figure 2 shows that even large excess of one of nitriles in cross-condensation cannot prevent formation of mixture of complexes. Therefore, the problem of products separation arises, which is typically solved by chromatographic methods.…”