Synthesis and characterization of the azido-bound five-coordinate high-spin iron(II) “picket fence” porphyrin complex

An Fe(II)-azido five-coordinate picket fence porphyrin complex with the formula [Na(2,2,2-crypt)][FeII(TpivPP)(N3)] · 3C6H5Cl (TpivPP = α,α,α,α-tetrakis(o-pivalamidophenyl)porphinato, known as a picket fence porphyrin, and 2,2,2-crypt is the cryptand-222) has been synthesized and characterized. The synthesis utilizes cryptand-222 to solubilize sodium azide in the preparation procedure. The UV–Vis and IR spectroscopic data are consistent with an azido ferrous porphyrinate. The X-ray structural analysis and the Mössbauer results indicate that the ion complex [FeII(TpivPP)(N3)]− is high-spin and has the (dxy)2(dxz)1(dyz)1(dz2)1(dx2-y2)1(dxy)2(dxz)1(dyz)1(dz2)1(dx2-y2)1 ground state electronic configuration.

The present work reports the synthesis, the spectroscopic data and the crystal structure of the Fe(II)-azido five-coordinate picket fence porphyrin complex [Na(2,2,2-crypt)][FeII(TpivPP)(N3)] · 3C6H5Cl (TpivPP = α,α,α,α-tetrakis(o-pivalamidophenyl)porphinato and 2,2,2-crypt is the cryptand-222). The Mössbauer and X-ray data are used to assign the ground state electronic configuration of the iron(II) high-spin (S = 2) central ion.Figure optionsDownload as PowerPoint slide