SYNTHESIS AND SOME REACTIONS OF ETA-5-PENTAMETHYLCYCLOPENTADIENYLNICKEL COMPLEXES

Reaction of Me5C5Li and Ni(CO)4 gave [(n5-Me5C5)Ni(CO)]2 (I) in 40 % yield. Reaction of I with iodine followed by addition of a tertiary phosphine or reaction of (PPh3)2NiX2 with Me5C5Li or Me5C5SnBu3 gave (n5-Me5C5)Ni(L)X (II) (L = tertiary phosphine, X = halogen). Treatment of II with RLi (R = Me, PhCC) afforded (n5-Me5C5)Ni(L)R (III). The spectroscopic properties and the reactivities of n5-pentamethylcyclopentadienylnickel complexes indicate that the n5-Me5C5 ligand is more electron-donating and a sterically more bulky than the n5-C5H5 ligand. © 1979.