Spontaneous Resolution by Crystallization of an Octanuclear Iron(III) Complex Using Only Racemic Reagents.

The P and M enantiomers of the octanuclear [Fe8 (μ4 -O)4 (μ-4-Cl-pz)12 Cl4 ] complex, having T symmetry, were resolved by temporary substitution of chloride ligands by racemic 4-s Bu-phenolates and subsequent crystallization, where the (S)- and (R)-phenolates coordinate selectively to the M and P complexes, respectively. The complexes were characterized by circular dichroism analysis and X-ray structure determination. This work constitutes a rare example of enantiomeric recognition resulting in spontaneous resolution upon crystallization.