Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1321954 | Journal of Organometallic Chemistry | 2013 | 8 Pages |
Cyclotriphosphazene and cyclotetraphosphazene appended with six and eight covalently linked porphyrin–ferrocene conjugates respectively were synthesized by treating N3P3Cl6 and N4P4Cl8 with appropriate equivalents of ferrocene linked porphyrin containing meso-hydroxyphenyl group in THF in the presence of Cs2CO3 followed by column chromatographic purification. NMR and absorption studies indicated a weak interaction between adjacent porphyrin–ferrocene conjugates. Electrochemical studies supported electrochemical equivalence of ferrocenyl and porphyrinyl moieties in these multi-porphyrin–ferrocene conjugate assemblies. The fluorescence studies showed significant quenching of porphyrin fluorescence due to photo-induced electron transfer from ferrocene to singlet state of porphyrin unit in these assemblies.
Graphical abstractSynthesis, spectral and electrochemical properties of cyclophosphazenes appended with porphyrin–ferrocene conjugates are described.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Multi-porphyrin–ferrocene conjugate assemblies on cyclophosphazenes were synthesized. ► Cyclophosphazene rings are robust and stable. ► Absorption studies showed three/four fold intensity enhancement. ► Electrochemical studies supported electrochemical equivalence of ferrocene units. ► Fluorescence quenching was attributed to photo-induced electron transfer.