Synthesis and characterization of new ferrocenyl-containing Tin(IV) and Indium(III) porphyrins.

Abstract

A series of new tin (IV) σ-bonded ferrocene-containing porphyrins, FcXSnTPP complexes (X = Fc or Cl; TPP = 5,10,15,20-tetraphenylporphyrin(2-)) and FcXSnOEP complexes (X = Fc or OEt; OEP = 5,10,15,20-octaethylporphyrin(2-)), have been prepared and characterized using 1H NMR, UV-Vis, and MCD spectroscopy. Structures of all target compounds were confirmed by single crystal X-ray analysis. The redox properties of these compounds were investigated using electrochemistry, spectroelectrochemistry, and chemical oxidation techniques. It has been found that the presence of one or more ferrocene groups leads to controlled redox behaviors that can have potential application in optical and fluorescent sensors. Three new indium(III) polyferrocenyl porphyrins (XInTFcP complexes [X = Cl, OH, or Fc; TFcP = 5,10,15,20- tetraferrocenylporphyrin(2-)] have also been prepared and investigated by the similar methods. Through redox property analysis, mixed-valence state formations were observed between Fe(II)-Fe(III) centers. The mixed-valence nature of these compounds makes them candidates for molecular electronics. DFT calculations were also performed in order to understand the electronic structure and its relation to the redox properties involved for some of the compounds