Two dinuclear iron(II) complexes K[Fe-2(L-1)(SCN)(4)]center dot 2(C3H8O) and [Fe-2(L-1)(SeCN)(3)(C5H5N)]center dot H2O are stabilised in the '[HS-LS]' state by a bis-tetradentate pyrazolate-based ligand
Juan Olguin, Guy NL Jameson, Sally Brooker
Dalton Transactions | ROYAL SOC CHEMISTRY | Published : 2011
Two air-sensitive dinuclear iron(II) complexes, K[Fe(II)(2)(L(1))(SCN)(4)]·2(C(3)H(8)O) (1) and [Fe(II)(2)(L(1))(SeCN)(3)(C(5)H(5)N)]·H(2)O (2), of 3,5-bis[N,N-bis(2-pyridylmethyl)aminomethyl]-1H-pyrazolate [(L(1))(-)] have been prepared. Interestingly, complex 1 is anionic, featuring four coordinated SCN(-) anions and a potassium counterion whereas complex 2 is neutral, containing a coordinated pyridine molecule and only three coordinated SeCN(-) anions. These are the first iron complexes reported for this type of ligand. Magnetic measurements and Mössbauer spectra show that both 1 and 2 are in a '[HS-LS]' mixed spin state between 300 and 2 K.
This work was supported by grants from the University of Otago and the MacDiarmid Institute, including the award of a MacDiarmid-funded PhD scholarship and subsequently the award of a University of Otago Publishing Bursary to JO. We thank Dr J.L. Tallon (Industrial Research Limited) and Drs V.A. Milway and J.A. Kitchen (Brooker group) for their help with obtaining the magnetic data.