The structure of 2-biphenylylferrocene

Abstract

Crystals of 2-biphenylylferrocene, C₅H₅·Fe·C₅H₄·C₆H ₅, are orthorhombic, a= 23·16, b= 5·92, c= 11·56 Å, Z= 4, space-group Pca2₁. The structure was determined with visual Cu-K_a data by Patterson and Fourier methods, and refined by least-squares, the final R being 0·15 for 313 observed reflexions. The cyclopentadienyl rings are eclipsed, the first six-membered ring of the biphenylyl group is rotated 43° out of the cyclopentadienyl plane, and the outer six-membered ring is rotated 58° out of the plane of the first six-membered ring. These rotations relieve the strain which would exist in a planar model for the C₅H₄·C₆H₄·C₆H ₅ group.