Synthesis and characterization of a hydrophilic conjugated 4+4 Re(I)-porphyrin metallacycle

• A trans-dipyridylporphyrin bearing two short polyoxyethylene chains has been prepared.
• Reaction of the porphyrin with a Re(I) complex forms a 4+4 metallacycle soluble in common organic solvents.
• The metallacycle has been fully characterized by NMR including 13C-NMR and VT 1H DOSY-NMR experiments.
• Spray deposition of the metallacycle on mica led to the formation of regular ring-like nano-structures.

The preparation and the full characterization, including the X-ray structure determination, of a polar trans-dipyridylporphyrin functionalized with two short polyoxyethylene chains is reported. Reaction of the porphyrin with a Re(I) complex yielded a 4+4 metallacycle showing an improved solubility and a lower tendency to aggregate with respect to analogous porphyrin cyclic derivatives. These properties allowed a full NMR characterization of the metallacycle including VT 1H DOSY-NMR experiments and, for the first time, the recording of a 13C-NMR spectrum giving further insight into the structural definition of these type of metallacycles. Spray deposition of the metallacycle on a heated mica substrate shows the formation of regular ring-like nano-structures which are not formed by the parent porphyrin.

The synthesis and the full NMR characterization, including VT 1H DOSY-NMR experiments and the 13C-NMR spectrum, of a new 4+4 Re(I)-porphyrin metallacycle is described. When sprayed on a heated mica substrate the metallacycle forms regular ring-like nano-structures which are not formed by the parent porphyrin.Figure optionsDownload as PowerPoint slide