Novel gallium (III) phthalocyanine derivatives–Synthesis, photophysics and photochemistry
- Chauke, Vongani, Ogunsipe, Abimbola, Durmus, Mahmut, Nyokong, Tebello
- Authors: Chauke, Vongani , Ogunsipe, Abimbola , Durmus, Mahmut , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/283118 , vital:55912 , xlink:href="https://doi.org/10.1016/j.poly.2007.01.016"
- Description: The syntheses of gallium(III) chloride phthalocyanine {(Cl)GaPc}, octaphenoxyphthalocyaninato gallium(III) chloride {(Cl)GaOPPc} and octakis(4-tert-butylphenoxy)phthalocyaninato gallium(III) chloride {(Cl)GaOTBPPc}; as well as their photophysical and photochemical parameters are hereby presented. Fluorescence quantum yields do not vary much among the three metallophthalocyanines (MPcs); therefore it was concluded that the effect of the substituents is not significant amongst (Cl)GaPc, (Cl)GaOPPc and (Cl)GaOTBPPc. Solvents effects, however, had an effect on the results. Triplet quantum yields were found to be lower in DMSO than in DMF and toluene. The rate constants for fluorescence, intersystem crossing and internal conversion as well as fluorescence and triplet lifetimes are reported. We have also reported photodegradation and singlet oxygen quantum yields. There was no clear correlation between the later parameters. It was, however, established that the three MPcs were stable.
- Full Text:
- Date Issued: 2007
- Authors: Chauke, Vongani , Ogunsipe, Abimbola , Durmus, Mahmut , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/283118 , vital:55912 , xlink:href="https://doi.org/10.1016/j.poly.2007.01.016"
- Description: The syntheses of gallium(III) chloride phthalocyanine {(Cl)GaPc}, octaphenoxyphthalocyaninato gallium(III) chloride {(Cl)GaOPPc} and octakis(4-tert-butylphenoxy)phthalocyaninato gallium(III) chloride {(Cl)GaOTBPPc}; as well as their photophysical and photochemical parameters are hereby presented. Fluorescence quantum yields do not vary much among the three metallophthalocyanines (MPcs); therefore it was concluded that the effect of the substituents is not significant amongst (Cl)GaPc, (Cl)GaOPPc and (Cl)GaOTBPPc. Solvents effects, however, had an effect on the results. Triplet quantum yields were found to be lower in DMSO than in DMF and toluene. The rate constants for fluorescence, intersystem crossing and internal conversion as well as fluorescence and triplet lifetimes are reported. We have also reported photodegradation and singlet oxygen quantum yields. There was no clear correlation between the later parameters. It was, however, established that the three MPcs were stable.
- Full Text:
- Date Issued: 2007
Photochemistry, photophysics and nonlinear optical parameters of phenoxy and tert-butylphenoxy substituted indium (III) phthalocyanines
- Chauke, Vongani, Durmus, Mahmut, Nyokong, Tebello
- Authors: Chauke, Vongani , Durmus, Mahmut , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/268823 , vital:54235 , xlink:href="https://doi.org/10.1016/j.jphotochem.2007.05.022"
- Description: This work hereby presents the syntheses, photochemistry and photophysics of octaphenoxy ((Cl)InOPPc) and octakis(4-tert-butylphenoxy)chloroindium ((Cl)InOTBPPc) phthalocyanines. Calculated nonlinear parameters of these complexes are compared with those of the corresponding GaPc derivatives and tetrasubstituted GaPc and InPc complexes. Fluorescence quantum yields do not vary much between (Cl)InOPPc and (Cl)InOTBPPc complexes in different solvents. High quantum yields of triplet state (ΦT ranging from 0.70 to 0.91 in dimethysulphoxide, DMSO) and singlet oxygen generation (ΦΔ, ranging from 0.61 to 0.79 in DMSO) were obtained. Short triplet lifetimes 50–60 μs were obtained in DMSO). The optical limiting threshold intensity (Ilim) for the InPc derivatives were calculated and compared with those of corresponding tetrasubstituted InPc and GaPc complexes. The latter were found to be better optical limiters.
- Full Text:
- Date Issued: 2007
- Authors: Chauke, Vongani , Durmus, Mahmut , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/268823 , vital:54235 , xlink:href="https://doi.org/10.1016/j.jphotochem.2007.05.022"
- Description: This work hereby presents the syntheses, photochemistry and photophysics of octaphenoxy ((Cl)InOPPc) and octakis(4-tert-butylphenoxy)chloroindium ((Cl)InOTBPPc) phthalocyanines. Calculated nonlinear parameters of these complexes are compared with those of the corresponding GaPc derivatives and tetrasubstituted GaPc and InPc complexes. Fluorescence quantum yields do not vary much between (Cl)InOPPc and (Cl)InOTBPPc complexes in different solvents. High quantum yields of triplet state (ΦT ranging from 0.70 to 0.91 in dimethysulphoxide, DMSO) and singlet oxygen generation (ΦΔ, ranging from 0.61 to 0.79 in DMSO) were obtained. Short triplet lifetimes 50–60 μs were obtained in DMSO). The optical limiting threshold intensity (Ilim) for the InPc derivatives were calculated and compared with those of corresponding tetrasubstituted InPc and GaPc complexes. The latter were found to be better optical limiters.
- Full Text:
- Date Issued: 2007
Photochemistry, photophysics and nonlinear optical parameters of phenoxy and tert-butylphenoxy substituted indium (III) phthalocyanines
- Chauke, Vongani, Durmus, Mahmut, Nyokong, Tebello
- Authors: Chauke, Vongani , Durmus, Mahmut , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/268787 , vital:54232 , xlink:href="https://doi.org/10.1016/j.jphotochem.2007.05.022"
- Description: This work hereby presents the syntheses, photochemistry and photophysics of octaphenoxy ((Cl)InOPPc) and octakis(4-tert-butylphenoxy)chloroindium ((Cl)InOTBPPc) phthalocyanines. Calculated nonlinear parameters of these complexes are compared with those of the corresponding GaPc derivatives and tetrasubstituted GaPc and InPc complexes. Fluorescence quantum yields do not vary much between (Cl)InOPPc and (Cl)InOTBPPc complexes in different solvents. High quantum yields of triplet state (ΦT ranging from 0.70 to 0.91 in dimethysulphoxide, DMSO) and singlet oxygen generation (ΦΔ, ranging from 0.61 to 0.79 in DMSO) were obtained. Short triplet lifetimes 50–60 μs were obtained in DMSO). The optical limiting threshold intensity (Ilim) for the InPc derivatives were calculated and compared with those of corresponding tetrasubstituted InPc and GaPc complexes. The latter were found to be better optical limiters.
- Full Text:
- Date Issued: 2007
- Authors: Chauke, Vongani , Durmus, Mahmut , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/268787 , vital:54232 , xlink:href="https://doi.org/10.1016/j.jphotochem.2007.05.022"
- Description: This work hereby presents the syntheses, photochemistry and photophysics of octaphenoxy ((Cl)InOPPc) and octakis(4-tert-butylphenoxy)chloroindium ((Cl)InOTBPPc) phthalocyanines. Calculated nonlinear parameters of these complexes are compared with those of the corresponding GaPc derivatives and tetrasubstituted GaPc and InPc complexes. Fluorescence quantum yields do not vary much between (Cl)InOPPc and (Cl)InOTBPPc complexes in different solvents. High quantum yields of triplet state (ΦT ranging from 0.70 to 0.91 in dimethysulphoxide, DMSO) and singlet oxygen generation (ΦΔ, ranging from 0.61 to 0.79 in DMSO) were obtained. Short triplet lifetimes 50–60 μs were obtained in DMSO). The optical limiting threshold intensity (Ilim) for the InPc derivatives were calculated and compared with those of corresponding tetrasubstituted InPc and GaPc complexes. The latter were found to be better optical limiters.
- Full Text:
- Date Issued: 2007
Photophysical and photochemical studies of long chain-substituted zinc phthalocyanines
- Durmus, Mahmut, Ahsen, Vefa, Nyokong, Tebello
- Authors: Durmus, Mahmut , Ahsen, Vefa , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/281310 , vital:55711 , xlink:href="https://doi.org/10.1016/j.jphotochem.2006.08.025"
- Description: Photochemical and photophysical measurements were conducted on peripheral and non-peripheral tetra(13,17-dioxanonacosane-15-hydroxy)-substituted zinc phthalocyanines (1, 2). General trends are described for quantum yields of photodegradation, fluorescence yields, triplet lifetimes and triplet quantum yields as well as singlet quantum yields of these compounds in dimethylformamide (DMF) and toluene. The effects of the solvents on the photophysical and photochemical parameters of the zinc(II) phthalocyanines (1, 2) are reported.
- Full Text:
- Date Issued: 2007
- Authors: Durmus, Mahmut , Ahsen, Vefa , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/281310 , vital:55711 , xlink:href="https://doi.org/10.1016/j.jphotochem.2006.08.025"
- Description: Photochemical and photophysical measurements were conducted on peripheral and non-peripheral tetra(13,17-dioxanonacosane-15-hydroxy)-substituted zinc phthalocyanines (1, 2). General trends are described for quantum yields of photodegradation, fluorescence yields, triplet lifetimes and triplet quantum yields as well as singlet quantum yields of these compounds in dimethylformamide (DMF) and toluene. The effects of the solvents on the photophysical and photochemical parameters of the zinc(II) phthalocyanines (1, 2) are reported.
- Full Text:
- Date Issued: 2007
Photophysical, photochemical and bovine serum albumin binding studies on water-soluble gallium (III) phthalocyanine derivatives
- Ogunsipe, Abimbola, Nyokong, Tebello, Durmus, Mahmut
- Authors: Ogunsipe, Abimbola , Nyokong, Tebello , Durmus, Mahmut
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/271239 , vital:54524 , xlink:href="https://doi.org/10.1142/S1088424607000746"
- Description: Spectral, photophysical, photochemical and bovine serum albumin binding studies on some gallium(III) derivatives - {1,(4)-(tetrapyridyloxyphthalocyaninato)gallium(III), (αGaPc); 2,(3)-(tetrapyridyloxyphthalocyaninato)gallium(III), (βGaPc); and their quaternized derivatives: QαGaPc and QβGaPc)} are hereby presented. β-Substituted complexes are more fluorescent, but show lower tendencies to undergo intersystem crossing than the α-substituted, as judged by their fluorescence and triplet quantum yield values. The quaternized derivatives (QGaPc) are water-soluble and non-aggregated, which makes them potential photosensitizers of choice for photodynamic therapy applications; these amphiphilic compounds also bind strongly to bovine serum albumin in 1:1 stoichiometries, and with binding constants (Kb) in the order of 106 M−1.
- Full Text:
- Date Issued: 2007
- Authors: Ogunsipe, Abimbola , Nyokong, Tebello , Durmus, Mahmut
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/271239 , vital:54524 , xlink:href="https://doi.org/10.1142/S1088424607000746"
- Description: Spectral, photophysical, photochemical and bovine serum albumin binding studies on some gallium(III) derivatives - {1,(4)-(tetrapyridyloxyphthalocyaninato)gallium(III), (αGaPc); 2,(3)-(tetrapyridyloxyphthalocyaninato)gallium(III), (βGaPc); and their quaternized derivatives: QαGaPc and QβGaPc)} are hereby presented. β-Substituted complexes are more fluorescent, but show lower tendencies to undergo intersystem crossing than the α-substituted, as judged by their fluorescence and triplet quantum yield values. The quaternized derivatives (QGaPc) are water-soluble and non-aggregated, which makes them potential photosensitizers of choice for photodynamic therapy applications; these amphiphilic compounds also bind strongly to bovine serum albumin in 1:1 stoichiometries, and with binding constants (Kb) in the order of 106 M−1.
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- Date Issued: 2007
Synthesis and photodynamic potential of tetra-and octa-triethyleneoxysulfonyl substituted zinc phthalocyanines
- Atilla, Devrim, Savdan, Nil, Durmus, Mahmut, Gürek, Ayşe Gül, Khan, Tania, Rück, Angelika, Walt, Heinrich, Nyokong, Tebello, Ahsen, Vefa
- Authors: Atilla, Devrim , Savdan, Nil , Durmus, Mahmut , Gürek, Ayşe Gül , Khan, Tania , Rück, Angelika , Walt, Heinrich , Nyokong, Tebello , Ahsen, Vefa
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/281342 , vital:55715 , xlink:href="https://doi.org/10.1016/j.jphotochem.2006.08.022"
- Description: Synthesis of the water soluble zinc phthalocyanines (3, 4) obtained from the phthalonitriles substituted with oligo(ethyleneoxy)thia groups are described. The new compounds have been characterized by elemental analysis, IR, 1H and 13C NMR spectroscopy, including HSQC, HMBC and COSY bidimensional correlation techniques, electronic spectroscopy and mass spectra. The aggregation behaviour of the phthalocyanine compounds (3, 4) was investigated using UV–vis spectroscopy in dimethylsulphoxide. Photochemical and photophysical measurements were conducted on oligo(ethyleneoxy)thia appended zinc phthalocyanines. General trends are described for quantum yields of photodegredation, fluorescence yields, triplet lifetimes and triplet quantum yields as well as singlet oxygen quantum yields of these compounds. The phototoxicity against cancer cells of the new compounds was investigated during several in vitro experiments. The dye-sensitized photooxidation of 1,3-diphenylisobenzofurane via 1O2 was studied in dimethylsulphoxide.
- Full Text:
- Date Issued: 2007
- Authors: Atilla, Devrim , Savdan, Nil , Durmus, Mahmut , Gürek, Ayşe Gül , Khan, Tania , Rück, Angelika , Walt, Heinrich , Nyokong, Tebello , Ahsen, Vefa
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/281342 , vital:55715 , xlink:href="https://doi.org/10.1016/j.jphotochem.2006.08.022"
- Description: Synthesis of the water soluble zinc phthalocyanines (3, 4) obtained from the phthalonitriles substituted with oligo(ethyleneoxy)thia groups are described. The new compounds have been characterized by elemental analysis, IR, 1H and 13C NMR spectroscopy, including HSQC, HMBC and COSY bidimensional correlation techniques, electronic spectroscopy and mass spectra. The aggregation behaviour of the phthalocyanine compounds (3, 4) was investigated using UV–vis spectroscopy in dimethylsulphoxide. Photochemical and photophysical measurements were conducted on oligo(ethyleneoxy)thia appended zinc phthalocyanines. General trends are described for quantum yields of photodegredation, fluorescence yields, triplet lifetimes and triplet quantum yields as well as singlet oxygen quantum yields of these compounds. The phototoxicity against cancer cells of the new compounds was investigated during several in vitro experiments. The dye-sensitized photooxidation of 1,3-diphenylisobenzofurane via 1O2 was studied in dimethylsulphoxide.
- Full Text:
- Date Issued: 2007
Synthesis and solvent effects on the electronic absorption and fluorescence spectral properties of substituted zinc phthalocyanines
- Durmus, Mahmut, Nyokong, Tebello
- Authors: Durmus, Mahmut , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/293279 , vital:57071 , xlink:href="https://doi.org/10.1016/j.poly.2007.01.018"
- Description: The synthesis and spectroscopic properties of the following tetra- and octa-substituted aryloxy zinc(II) phthalocyanines are reported for the first time: 1,(4)-(tetrabenzyloxyphenoxyphthalocyaninato) zinc(II) (7); 2,(3)-(tetrabenzyloxyphenoxyphthalocyaninato) zinc(II) (8); 2,3-(octabenzyloxyphenoxyphthalocyaninato) zinc(II) (9). The new compounds have been characterized by elemental analysis, IR, 1H NMR spectroscopy and electronic spectroscopy. Spectroscopic properties of these compounds were investigated in different solvents. Protonation of non-peripherally substituted complex 7 resulted in the splitting and red-shifting of the Q-band. The peripherally substituted derivatives 8 and 9, did not show the split in the Q-band. Fluorescence spectra of the derivatives show Stokes shifts typical of MPc complexes.
- Full Text:
- Date Issued: 2007
- Authors: Durmus, Mahmut , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/293279 , vital:57071 , xlink:href="https://doi.org/10.1016/j.poly.2007.01.018"
- Description: The synthesis and spectroscopic properties of the following tetra- and octa-substituted aryloxy zinc(II) phthalocyanines are reported for the first time: 1,(4)-(tetrabenzyloxyphenoxyphthalocyaninato) zinc(II) (7); 2,(3)-(tetrabenzyloxyphenoxyphthalocyaninato) zinc(II) (8); 2,3-(octabenzyloxyphenoxyphthalocyaninato) zinc(II) (9). The new compounds have been characterized by elemental analysis, IR, 1H NMR spectroscopy and electronic spectroscopy. Spectroscopic properties of these compounds were investigated in different solvents. Protonation of non-peripherally substituted complex 7 resulted in the splitting and red-shifting of the Q-band. The peripherally substituted derivatives 8 and 9, did not show the split in the Q-band. Fluorescence spectra of the derivatives show Stokes shifts typical of MPc complexes.
- Full Text:
- Date Issued: 2007
Synthesis and solvent effects on the electronic absorption and fluorescence spectral properties of substituted zinc phthalocyanines
- Durmus, Mahmut, Nyokong, Tebello
- Authors: Durmus, Mahmut , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/283140 , vital:55914 , xlink:href="https://doi.org/10.1016/j.poly.2007.01.018"
- Description: The synthesis and spectroscopic properties of the following tetra- and octa-substituted aryloxy zinc(II) phthalocyanines are reported for the first time: 1,(4)-(tetrabenzyloxyphenoxyphthalocyaninato) zinc(II) (7); 2,(3)-(tetrabenzyloxyphenoxyphthalocyaninato) zinc(II) (8); 2,3-(octabenzyloxyphenoxyphthalocyaninato) zinc(II) (9). The new compounds have been characterized by elemental analysis, IR, 1H NMR spectroscopy and electronic spectroscopy. Spectroscopic properties of these compounds were investigated in different solvents. Protonation of non-peripherally substituted complex 7 resulted in the splitting and red-shifting of the Q-band. The peripherally substituted derivatives 8 and 9, did not show the split in the Q-band. Fluorescence spectra of the derivatives show Stokes shifts typical of MPc complexes.
- Full Text:
- Date Issued: 2007
- Authors: Durmus, Mahmut , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/283140 , vital:55914 , xlink:href="https://doi.org/10.1016/j.poly.2007.01.018"
- Description: The synthesis and spectroscopic properties of the following tetra- and octa-substituted aryloxy zinc(II) phthalocyanines are reported for the first time: 1,(4)-(tetrabenzyloxyphenoxyphthalocyaninato) zinc(II) (7); 2,(3)-(tetrabenzyloxyphenoxyphthalocyaninato) zinc(II) (8); 2,3-(octabenzyloxyphenoxyphthalocyaninato) zinc(II) (9). The new compounds have been characterized by elemental analysis, IR, 1H NMR spectroscopy and electronic spectroscopy. Spectroscopic properties of these compounds were investigated in different solvents. Protonation of non-peripherally substituted complex 7 resulted in the splitting and red-shifting of the Q-band. The peripherally substituted derivatives 8 and 9, did not show the split in the Q-band. Fluorescence spectra of the derivatives show Stokes shifts typical of MPc complexes.
- Full Text:
- Date Issued: 2007
Synthesis, photophysical and photochemical properties of aryloxy tetra-substituted gallium and indium phthalocyanine derivatives
- Durmus, Mahmut, Nyokong, Tebello
- Authors: Durmus, Mahmut , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/281431 , vital:55724 , xlink:href="https://doi.org/10.1016/j.tet.2006.11.089"
- Description: The synthesis, photophysical and photochemical properties of the tetra-substituted aryloxy gallium(III) and indium(III) phthalocyanines are reported for the first time. General trends are described for photodegradation, singlet oxygen, fluorescence, and triplet quantum yields and triplet lifetimes of these compounds. The introduction of phenoxy and tert-butylphenoxy substituents on the ring resulted in lowering of fluorescence quantum yields and lifetimes, and triplet quantum yields, and an increase of kIC, kISC, and kF. Photoreduction of the complexes was observed during laser flash photolysis. The singlet oxygen quantum yields (ΦΔ), which give an indication of the potential of the complexes as photosensitizers in applications where singlet oxygen is required (Type II mechanism) ranged from 0.41 to 0.91. Thus, these complexes show potential as Type II photosensitizers.
- Full Text:
- Date Issued: 2007
- Authors: Durmus, Mahmut , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/281431 , vital:55724 , xlink:href="https://doi.org/10.1016/j.tet.2006.11.089"
- Description: The synthesis, photophysical and photochemical properties of the tetra-substituted aryloxy gallium(III) and indium(III) phthalocyanines are reported for the first time. General trends are described for photodegradation, singlet oxygen, fluorescence, and triplet quantum yields and triplet lifetimes of these compounds. The introduction of phenoxy and tert-butylphenoxy substituents on the ring resulted in lowering of fluorescence quantum yields and lifetimes, and triplet quantum yields, and an increase of kIC, kISC, and kF. Photoreduction of the complexes was observed during laser flash photolysis. The singlet oxygen quantum yields (ΦΔ), which give an indication of the potential of the complexes as photosensitizers in applications where singlet oxygen is required (Type II mechanism) ranged from 0.41 to 0.91. Thus, these complexes show potential as Type II photosensitizers.
- Full Text:
- Date Issued: 2007
Synthesis, Photophysical and Photochemical Properties of Poly (oxyethylene)‐Substituted Phthalocyaninato Oxotitanium (IV) Complexes
- Atilla, Devrim, Durmus, Mahmut, Yılmaz, Özgür, Gürek, Ayşe Gül, Ahsen, Vefa, Nyokong, Tebello
- Authors: Atilla, Devrim , Durmus, Mahmut , Yılmaz, Özgür , Gürek, Ayşe Gül , Ahsen, Vefa , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/271263 , vital:54526 , xlink:href="https://doi.org/10.1002/ejic.200700057"
- Description: The synthesis, photophysical and photochemical properties of tetra- and chlorotetrapoly(oxyethylene)-substituted oxotitanium(IV) phthalocyanines are reported for the first time. The new compounds were characterized by elemental analysis, IR, 1H and 13C NMR spectroscopy, electronic spectroscopy and mass spectra. These complexes showed monomeric behaviour in solution. General trends are described for photodegredation, singlet oxygen, triplet state and fluorescence quantum yields, and triplet and fluorescence lifetimes of these compounds in dimethyl sulfoxide (DMSO). Photophysical and photochemical properties of phthalocyanine complexes are very useful for PDT applications. The complexes showed high triplet quantum yields and triplet lifetimes in DMSO. The singlet oxygen quantum yields (ΦΔ), which give an indication of the potential of the complexes as photosensitizers in applications where singlet oxygen is required (Type II mechanism), were 0.72 and 0.78 for 3a and 5a, respectively. Thus, these complexes show potential as Type II photosensitizers. These complexes were also quenched by benzoquinone for fluorescence quenching studies.
- Full Text:
- Date Issued: 2007
- Authors: Atilla, Devrim , Durmus, Mahmut , Yılmaz, Özgür , Gürek, Ayşe Gül , Ahsen, Vefa , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/271263 , vital:54526 , xlink:href="https://doi.org/10.1002/ejic.200700057"
- Description: The synthesis, photophysical and photochemical properties of tetra- and chlorotetrapoly(oxyethylene)-substituted oxotitanium(IV) phthalocyanines are reported for the first time. The new compounds were characterized by elemental analysis, IR, 1H and 13C NMR spectroscopy, electronic spectroscopy and mass spectra. These complexes showed monomeric behaviour in solution. General trends are described for photodegredation, singlet oxygen, triplet state and fluorescence quantum yields, and triplet and fluorescence lifetimes of these compounds in dimethyl sulfoxide (DMSO). Photophysical and photochemical properties of phthalocyanine complexes are very useful for PDT applications. The complexes showed high triplet quantum yields and triplet lifetimes in DMSO. The singlet oxygen quantum yields (ΦΔ), which give an indication of the potential of the complexes as photosensitizers in applications where singlet oxygen is required (Type II mechanism), were 0.72 and 0.78 for 3a and 5a, respectively. Thus, these complexes show potential as Type II photosensitizers. These complexes were also quenched by benzoquinone for fluorescence quenching studies.
- Full Text:
- Date Issued: 2007
Synthesis, photophysical and photochemical properties of tetra-and octa-substituted gallium and indium phthalocyanines
- Durmus, Mahmut, Nyokong, Tebello
- Authors: Durmus, Mahmut , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/271276 , vital:54529 , xlink:href="https://doi.org/10.1016/j.poly.2007.03.007"
- Description: The synthesis, photophysical and photochemical properties of the tetra- and octa-[4-(benzyloxyphenoxy)] substituted gallium(III) and indium(III) phthalocyanines are reported for the first time. The new compounds have been characterized by elemental analysis, IR, 1H NMR spectroscopy and electronic spectroscopy. General trends are described for quantum yields of photodegredation, fluorescence quantum yields and lifetimes, triplet lifetimes and triplet quantum yields as well as singlet oxygen quantum yields of these compounds in dimethylsulfoxide (DMSO). Substituted indium phthalocyanine complexes (7b–9b) showed much higher quantum yields of triplet state and shorter triplet lifetimes, compared to the substituted GaPc derivatives due to enhanced intersystem crossing (ISC) in the former. The gallium and indium phthalocyanine complexes showed phototransformation during laser irradiation due to ring reduction. The singlet oxygen quantum yields (ΦΔ), which give an indication of the potential of the complexes as photosensitizers in applications where singlet oxygen is required (Type II mechanism) ranged from 0.51 to 0.94. Thus, these complexes show potential as photodynamic therapy of cancer.
- Full Text:
- Date Issued: 2007
- Authors: Durmus, Mahmut , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/271276 , vital:54529 , xlink:href="https://doi.org/10.1016/j.poly.2007.03.007"
- Description: The synthesis, photophysical and photochemical properties of the tetra- and octa-[4-(benzyloxyphenoxy)] substituted gallium(III) and indium(III) phthalocyanines are reported for the first time. The new compounds have been characterized by elemental analysis, IR, 1H NMR spectroscopy and electronic spectroscopy. General trends are described for quantum yields of photodegredation, fluorescence quantum yields and lifetimes, triplet lifetimes and triplet quantum yields as well as singlet oxygen quantum yields of these compounds in dimethylsulfoxide (DMSO). Substituted indium phthalocyanine complexes (7b–9b) showed much higher quantum yields of triplet state and shorter triplet lifetimes, compared to the substituted GaPc derivatives due to enhanced intersystem crossing (ISC) in the former. The gallium and indium phthalocyanine complexes showed phototransformation during laser irradiation due to ring reduction. The singlet oxygen quantum yields (ΦΔ), which give an indication of the potential of the complexes as photosensitizers in applications where singlet oxygen is required (Type II mechanism) ranged from 0.51 to 0.94. Thus, these complexes show potential as photodynamic therapy of cancer.
- Full Text:
- Date Issued: 2007
Synthesis, photophysical and photochemical studies of new water-soluble indium (III) phthalocyanines
- Durmus, Mahmut, Nyokong, Tebello
- Authors: Durmus, Mahmut , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/283976 , vital:56007 , xlink:href="https://doi.org/10.1039/b618478b"
- Description: The preparation of water-soluble indium(III)phthalocyanine complexes is described for the first time in this study. Peripherally and non-peripherally 3-hydroxypyridine tetrasubstituted indium(III) phthalocyanines (5a, 6a) and their quaternarized derivatives (5b, 6b) have been synthesized and characterized by elemental analysis, IR, 1H NMR spectroscopy, electronic spectroscopy and mass spectra. The quaternarized compounds (5b, 6b) show excellent solubility in water, which makes them potential photosensitizers for use in photodynamic therapy (PDT) applications. Photochemical and photophysical measurements were conducted on 3-pyridyloxy appended indium(III) phthalocyanines in dimethylsulfoxide (DMSO) for non-ionic (5b, 6b) derivatives. General trends are described for quantum yields of photodegradation, fluorescence lifetimes, fluorescence quantum yields, triplet lifetimes and triplet quantum yields as well as singlet oxygen quantum yields of these compounds. The singlet oxygen quantum yields (ΦΔ), which give an indication of the potential of the complexes as photosensitizers in applications where singlet oxygen is required (Type II mechanism) are very high (ΦΔ > 0.55). Thus, these complexes may be useful as Type II photosensitizers.
- Full Text:
- Date Issued: 2007
Synthesis, photophysical and photochemical studies of new water-soluble indium (III) phthalocyanines
- Authors: Durmus, Mahmut , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/283976 , vital:56007 , xlink:href="https://doi.org/10.1039/b618478b"
- Description: The preparation of water-soluble indium(III)phthalocyanine complexes is described for the first time in this study. Peripherally and non-peripherally 3-hydroxypyridine tetrasubstituted indium(III) phthalocyanines (5a, 6a) and their quaternarized derivatives (5b, 6b) have been synthesized and characterized by elemental analysis, IR, 1H NMR spectroscopy, electronic spectroscopy and mass spectra. The quaternarized compounds (5b, 6b) show excellent solubility in water, which makes them potential photosensitizers for use in photodynamic therapy (PDT) applications. Photochemical and photophysical measurements were conducted on 3-pyridyloxy appended indium(III) phthalocyanines in dimethylsulfoxide (DMSO) for non-ionic (5b, 6b) derivatives. General trends are described for quantum yields of photodegradation, fluorescence lifetimes, fluorescence quantum yields, triplet lifetimes and triplet quantum yields as well as singlet oxygen quantum yields of these compounds. The singlet oxygen quantum yields (ΦΔ), which give an indication of the potential of the complexes as photosensitizers in applications where singlet oxygen is required (Type II mechanism) are very high (ΦΔ > 0.55). Thus, these complexes may be useful as Type II photosensitizers.
- Full Text:
- Date Issued: 2007
The synthesis, fluorescence behaviour and singlet oxygen studies of new water-soluble cationic gallium (III) phthalocyanines
- Durmus, Mahmut, Nyokong, Tebello
- Authors: Durmus, Mahmut , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/280207 , vital:55586 , xlink:href="https://doi.org/10.1016/j.inoche.2006.11.012"
- Description: The preparation of cationic water-soluble gallium phthalocyanine derivatives are described for the first time. Peripheral and non-peripheral 3-hydroxypyridine tetrasubstituted gallium(III)phthalocyanines (5a, 6a) and their quaternarized derivatives (5b and 6b) have been synthesized and characterized by elemental analysis, IR, 1H NMR spectroscopy, electronic spectroscopy and mass spectra. The quaternarized compounds (5b and 6b) are soluble in water and not aggregated (in water and in organic solvents) within a wide concentration range. General trends are described for singlet oxygen quantum yields, fluorescence quantum yields and fluorescence lifetimes of these compounds. These complexes showed better singlet oxygen quantum yields in water than the related quarternarized porphyrazine complexes.
- Full Text:
- Date Issued: 2007
- Authors: Durmus, Mahmut , Nyokong, Tebello
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/280207 , vital:55586 , xlink:href="https://doi.org/10.1016/j.inoche.2006.11.012"
- Description: The preparation of cationic water-soluble gallium phthalocyanine derivatives are described for the first time. Peripheral and non-peripheral 3-hydroxypyridine tetrasubstituted gallium(III)phthalocyanines (5a, 6a) and their quaternarized derivatives (5b and 6b) have been synthesized and characterized by elemental analysis, IR, 1H NMR spectroscopy, electronic spectroscopy and mass spectra. The quaternarized compounds (5b and 6b) are soluble in water and not aggregated (in water and in organic solvents) within a wide concentration range. General trends are described for singlet oxygen quantum yields, fluorescence quantum yields and fluorescence lifetimes of these compounds. These complexes showed better singlet oxygen quantum yields in water than the related quarternarized porphyrazine complexes.
- Full Text:
- Date Issued: 2007
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