Synthesis, Resolution, and Crystallographic Characterization of a C2-Symmetric Diphosphaferrocene

Treatment of FeCl2 with potassium 2-phenyl-3,4-dimethylphospholide provides a new C2-symmetric diphosphaferrocene, (±)-3,3',4,4'-tetramethyl-2,2'-diphenyl-1,1'-diphosphaferrocene (1). Separation by chiral HPLC furnishes both antipodes of complex 1, the first diphosphaferrocene to be prepared in enantiopure form. The absolute configuration of (−)-1 has been determined by X-ray crystallography.