Glatz, M., Gorgas, N., Stöger, B., Pittenauer, E., Ferreira, L. P., Veiros, L. F., Calhorda, M. J., & Kirchner, K. (2021). Structural and Electronic Properties of Iron(0) PNP Pincer Complexes. Journal of Inorganic and General Chemistry, 647(14), 1429–1435. https://doi.org/10.1002/zaac.202100015
In the present work we have prepared and fully characterized several Fe(0) complexes of the type [Fe(PNP)(CO)2] treating Fe(II) complexes [Fe(PNP)(Cl)2] with KC8 in the presence of carbon monoxide. While complexes [Fe(PNPNMe-iPr)(CO)2], [Fe(PNPNEt-iPr)(CO)2] adopt a trigonal bipyramidal geometry, the bulkier and more electron rich [Fe(PNPNH-tBu)(CO)2] is closer to a square pyramidal geometry. Mössbauer spectra showed isomer shifts very close to 0 and similar to those reported for Fe(I) systems. Quadrupole splitting values range between 2.2 and 2.7 mm s⁻¹ both in experiments and DFT calculations, while those of Fe(I) complexes are much smaller (∼0.6 mm s⁻¹).
