Inorganic Chemistry, Vol.51, No.4, 1980-1982, 2012
Fe-4 Cluster and a Buckled Macrocycle Complex from the Reduction of [(dmgBF(2))(2)Fe(L)(2)] (L = MeCN, (BuNC)-Bu-t-N-i)
We report the syntheses, X-ray structures, and reductive electrochemistry of the Fe-II complexes [(dmgBF(2))(2)Fe(MeCN)(2)] (1; dmg = dimethylglyoxime, MeCN = acetonitrile) and [(dmgBF(2))Fe((BuNC)-Bu-t-N-i)(2)] (2; (BuNC)-Bu-t-N-i = tert-butylisocyanide). The reaction of 1 with Na/Hg amalgam led to isolation and the X-ray structure of [(dmgBF(2))(2)Fe(glyIm)] (3; glyIm = glyimine), wherein the (dmgBF(2))(2) macrocyclic frame is bent to accommodate the binding of a bidentate apical ligand. We also report the Xray structure of a rare mixed-valence Fe-4 cluster with supporting dmg-type ligands. In the structure of [(dmg(2)BF(2))(3)Fe-3(1/2dmg)(3)Fe(O)(6)] (4), the (dmgBF(2))(2) macrocycle has been cleaved, eliminating BF2 groups. Density functional theory calculations and electron paramagnetic resonance data are in accordance with a central Fe-III ion surrounded by three formally Fe(II)dmg(2)BF(2) units.