The Crystal and Molecular Structure of Tris(π-cyclopentadienyl nickel) tertiary-butylammonium

The crystal structure of tris(π-cyclopentadienylnickel)tertiary-butylammonium, t-C4H9N(π-C5H5Ni)3, has been determined from single crystal X-ray diffractometer data. The space group is C2/c and the lattice constants are a=28.40 A, b=9.16 A, c=15.28 A, β=100°30′, and Z=8. The refinement was carried out using block-diagonal least-squares calculation including anisotropic temperature factors for the three nickel atoms. The final R index for 1620 reflections is 0.138. The molecule is of approximately a trigonal pyramidal structure with an apical nitrogen atom on a triangle of the nickel atoms. The interatomic distances are 2.33–2.39 A for nickel to nickel, 1.93–1.98 A for nickel to nitrogen. The distances between a nickel atom and a centroid of a cyclopentadienyl ring are 1.74–1.81 A. The three cyclopentadienyl rings are inclined to the nickel triangle plane at 68°–69°.