1236907-70-2Relevant academic research and scientific papers
Redox chemistry of bis(phosphaethenyl)pyridine iron complexes
Nakajima, Yumiko,Ozawa, Fumiyuki
, p. 2009 - 2015 (2012/04/23)
Redox reactions of iron complexes bearing a PNP-pincer-type phosphaalkene ligand, 2,6-bis[1-phenyl-2-(2,4,6-tri-tert-butylphenyl)-2-phosphaethenyl] pyridine (BPEP), are reported. The Fe(II) dibromide [FeBr2(BPEP)] (1) is readily reduced by [Cp2Co] to afford the four-coordinate Fe(I) monobromide [FeBr(BPEP)] (2), while 2 reacts with PhCH2Br to reproduce 1. Treatment of 1 with MesMgBr or Mes2Mg(THF)2 (Mes = 2,4,6-Me3C6H2) results in one-electron reduction of 1, followed by transmetalation of the resulting 2 with mesitylmagnesium compounds to give the Fe(I) mesityl complex [FeMes(BPEP)] (3). The single-crystal diffraction study of 3 has revealed a distorted trigonal monopyramidal arrangement around the iron center. SQUID magnetometry has established a low-spin ground state (S = 1/2) of 3. Complex 2 reacts with Me2Mg(THF)2 to afford Fe(0) and Fe(II) complexes (4 and 5, respectively) coordinated with novel multidentate ligand systems containing a phosphonium ylide structure. The formation processes of 4 and 5 via an [FeMe(BPEP)] intermediate are discussed on the basis of their X-ray structures.
Electronic structure of four-coordinate iron(I) complex supported by a bis(phosphaethenyl)pyridine ligand
Nakajima, Yumiko,Nakao, Yoshihide,Sakaki, Shigeyoshi,Tamada, Yoshinori,Ono, Teruo,Ozawa, Fumiyuki
, p. 9934 - 9936 (2010/10/04)
A 15-electron iron complex with a formal Fe(I) center, [FeBr(BPEP)] (BPEP) 2,6-bis(1-phenyl-2-phosphaethenyl)pyridine), was prepared by one-electron reduction of the dibromide precursor [FeBr2(BPEP)]. The single-crystal diffraction analysis revealed a distorted trigonal monopyramidal arrangement around the iron center, and SQUID magnetometry established the S) 3/2 ground state. The Moessbauer isomer shift value (δ) 0.59 mm/s) was consistent with a high-spin Fe(I) center of [FeBr(BPEP)]. DFT calculations for a model complex revealed two highly delocalized molecular orbitals formed by bonding and antibonding interactions between the dZ2 (Fe) and π* (BPEP) orbitals. Orbital occupancy analysis demonstrated the electronic structure with a high-spin Fe(I) center. The effective dπ-pπ interaction between iron and BPEP was concluded to be responsible for the highly distorted structure of [FeBr(BPEP)], with its rather uncommon trigonal monopyramidal configuration.
