BINUCLEAR ZIRCONIUM(III) AND ZIRCONIUM(IV) COMPLEXES - MILD OXIDATION OF LOW-VALENT ZIRCONIUM AS A SYNTHETIC PATHWAY TO A CLASS OF TRIVALENT AND TETRAVALENT ZIRCONIUM FULVALENE COMPLEXES - MOLECULAR-STRUCTURES OF [ETA-5-ETA-5-C10H8][CPZRSPH]2, [ETA-5-ETA-5-C10H8][CPZR(CH3)2]2, AND [ETA-5-ETA-5-C10H8][CPZR]2[MU-S]2

The oxidation of [CpZr(PMe3)(η1:η5-C5H4)]2 (1) with several reagents (R3PX2 (R = n-Bu, Me; X = Cl, Br, I), PhSSPh, Me2PPMe2) afforded the reductive coupling of the two bridging η1:η5-C5H4 rings. The reaction allowed the large-scale preparation of a class of fulvalene-containing cis-Zr(III) [η5:η5-C10H8][CpZrX]2 (X = Cl (3), Br (4), I (5), SPh (6), PMe2 (7)) and trans-Zr(IV) [η5:η5-C10H8][CpZrX2]2 (X = Cl (8), I (9), SPh (10), Me (11)) complexes with respect to the plane of the fulvalene ligand. The cis-(fulvalene)Zr(IV) complex [η5:η5-C10H8][CpZrS]2 (12) was obtained upon treatment of 1, 6, or 11 with S8. Crystal data for 6, 11, and 12 are as follows: 6, C32H28Zr2S2, monoclinic, space group P2l/n, with a = 9.929 (1) Å, b = 16.017 (1) Å, c = 16.641 (1) Å, β = 97.67 (1)°, Z = 4, and R = 0.031 (Rw = 0.031); 11, C24H30Zr2, orthorhombic, space group Pca21 with a = 14.694 (1) Å, b = 11.381 (1) Å, c = 13.026 (2) Å, Z = 4, and R = 0.058 (Rw = 0.064); 12, C20H18Zr2S2, orthorhombic, space group Fdd2, with a = 22.523 (2) Å, b = 20.446 (2) Å, c = 8.001 (1) Å, Z = 8, and R = 0.023 (Rw - 0.025). A double-carbonylation reaction of 11 led to the formation of the binuclear bis(acyl) derivative [η5:η5-C10H8][CpZrMe(COMe)]2. © 1990, American Chemical Society. All rights reserved.