Metall‐π‐Komplexe von Benzolderivaten, 36. Zur Kenntnis der Struktur von μ(η 6 :η 6 ‐Biphenyl)bis[(η 6 ‐benzol)metall]‐Komplexen in starrer Lösung und im Kristall

Metal π‐Complexes of Benzene Derivatives, 36. — The Structure of μ(η 6 :η 6 ‐Biphenyl)bis[(η 6 ‐benzene)metal] Complexes in Rigid Solution and in the Crystalline State For μ(η 6 :η 6 ‐C 6 H 5 C 6 H 5 )[η 6 ‐C 6 H 6 )Cr] 2 ( 2 ) an antiperiplanar conformation has been established by means of X‐ray diffraction. Two (C 6 H 6 )Cr units coordinate to planar bridging biphenyl. This configuration differs from that of the diradical dication 2 d⊕ d⊕ in rigid solution. According to the zero‐field splitting parameter D in the EPR spectrum, 2 d⊕ d⊕ adopts a synclinal conformation, the half‐sandwich fragments coordinating to twisted biphenyl (dihedral angle α ≈ 60°).