Complex 6 is extremely air sensitive and decomposes in solution over a few days. ppm, reflecting C1 symmetry in solution. We were unable to assign resonances to specific proton environments due to peak broadness and overlapping in the 0 to 8 ppm region (Figure ). Despite the complexity of the 1 H NMR spectrum and crystal structure, the solid-state Mössbauer spectrum of 6 (Figure ) has a single quadrupole doublet with an isomer shift similar to that of the starting material (0.34 mm/s for 6 vs. 0.35 mm/s for 5-Et2O), but a smaller quadrupole splitting (1.87 mm/s for 6 vs. 3.91 mm/s for 5-Et2O). The Mössbauer spectrum suggests that all iron sites are equivalent.