129707-64-8Relevant academic research and scientific papers
Synthesis and photoproperties of diamagnetic octabutoxyphthalocyanines with deep red optical absorbance
Rihter, Boris D.,Kenney, Malcolm E.,Ford, William E.,Rodgers, Michael A. J.
, p. 8064 - 8070 (2007/10/02)
The synthesis and photoproperties of six new metal 1,4,8,11,15,18,22,25-octabutoxyphthalocyanines and photoproperties of the known analogous Zn and metal-free phthalocyanines are described. The new compounds are AIPc(OBu)8OSiEt3, GaPc(OBu)8OSiEt3, GePc(OBu)8(OSiEt3)2, SnPc(OBu)8(OSiEt3)2, RuPc(OBu)8(py)2, and PdPc(OBu)8 (where Pc(OBu)8 represents the octabutoxyphthalocyanine ligand). Benzene-d6 solutions of all eight of the compounds give NMR spectra showing large ring-current effects. Benzene solutions of the compounds give visible spectra with absorption maxima in the 688-779-nm range having extinction coefficients between 1.0 × 105 and 2.2 × 105 M-1cm-1. The triplet-state properties of the phthalocyanines in benzene solutions have been measured by laser flash photolysis. The triplet states have absorption maxima in the 550-640-nm range, quantum yields in the 0.1-0.9 range, and lifetime when the solutions are deaerated in the 0.5-150-μs range. The rate constants for energy transfer from the triplet states of the compounds to O2 are between 1.3 × 108 and 2.8 × 109 M-1 s-1. Analysis of kinetic data pertaining to the photogeneration of O2 (1Δg) by the main-group compounds shows that the energy gap between their singlet (S1) and triplet (T1) states is 14.9 ± 0.3 kcal/mol. Relationships between the photoproperties of the metal complexes and the position in the periodic chart of the metals they contain are apparent.
