Preparations and Photosensitizing Properties of 2,7,12,17-Tetra-n-propylporphycenatotin(IV) Dihalide Complexes

Abstract

2,7,12,17-Tetra-n-propylporphycenatodihalotin(IV) complexes ([Sn(TPrPc)X2], X = F, Cl, and Br) were synthesized and their photophysical properties were investigated. These complexes exhibit strong absorptions in the red region (600–630 nm). Strong quenching was observed during the fluorescence emission of the dibromotin(IV) complex, which is caused by an intramolecular heavy-atom effect. The complexes emit NIR phosphorescence in 1-iodopropane at room temperature and the intensity of the emission of the dibromotin(IV) complex is found to be smaller than that of the dichlorotin(IV) complex. The quantum efficiency (ΦΔ) of generation of singlet oxygen using the dibromotin(IV) complex is the highest among the porphycenatotin(IV) complexes (ΦΔ = 0.79). Photooxidation of 1,3-diphenylisobenzofuran catalyzed by the complexes upon irradiation with red light (over 600 nm) was studied and a rapid oxidation of the substrate was observed when using the dibromotin(IV) complex.

Spectroscopy and Tautomerization Studies of Porphycenes

“…Hexacoordinated complexes of porphycenes with tin have been described for 1 , 13 , and 19 . , Dihalide complexes of 13 -Sn­(IV) exhibit strong absorption in the Q region. They are also good photosensitizers, which was demonstrated by their ability to catalyze the photooxidation of 1,3-diphenylisobenzofuran …”

“…They are also good photosensitizers, which was demonstrated by their ability to catalyze the photooxidation of 1,3-diphenylisobenzofuran. 156 Guilard and Kadish and co-workers reported pentacoordinated alumina complexes 218 134,159 platinum (13), 150,162 molybdenum (19), 163 and magnesium (19). 164 2.1.6.…”

Porphycene-mediated photooxidation of benzylamines by visible light

“…11 Additionally, tetrapropylporphycenato tin(IV) chloride and bromide complexes were recently reported as efficient photosensitizers in photooxidation of 1,3diphenylisobenzofuran. 12 The oxidation products of amines involving imines are important substrates in the synthesis of biologically active molecules containing nitrogen. 13 Desired methods for imine synthesis should be mild and efficient.…”