Olefin Polymerization Activity and Crystal Structure of Alkyliron(Ⅲ) Porphyrin Complexes

Abstract

Alkyliron(III) porphyrins, n-butyliron(III) tetraphenylporphyrin, (TPP)Fe-Bu and n-butyliron(III) tetrakis-(pentafluorophenyl)porphyrin, (F 20 TPP)Fe-Bu have been evaluated as suitable for olefin free-radical polymerization. Butyl radicals dissociated from n-butyliron(III) porphyrin initiated the polymerization reaction, but the ratio of the propagation was low. The GCMS analysis of the reaction mixture of nbutyliron(III) porphyrin and styrene has revealed several products containing two butyl groups, while traces of β-hydrogen-abstracted products were observed. The crystal structure of (TPP)Fe-Bu has been determined. The structure of the n-butyliron(III) porphyrin reveals the compound containing five-coordinated iron with the average Fe-N distance of 1.973(1) Å and Fe-C of 2.030(2) Å. The iron atom is displaced by 0.137Å from a four nitrogen mean plane. Crystal system is triclinic, and space group is P-1.