PENTAMETHYLCYCLOPENTADIENYL-AMINOBOROLE DERIVATIVES OF ZIRCONIUM AND HAFNIUM WITH ALKYL AND ALLYL LIGANDS

The preparations of new alkyl, iodo, and allyl derivatives of zirconiu m and hafnium with pentamethylcyclopentadienyl and aminoborole ancilla ry ligands are described. The dialkyl complexes Cp {eta(5)-C4H4BN(CH Me(2))(2))ZrR(2)Li (R = Me, C = C-p-C6H4CH3, C = CMe(3), CH(2)Ph) are prepared from Cp (eta(5)-C4H4BN(CHMe(2))(2)}ZrCl . LiCl and two equi valents of RLi. Cp ZrI3 is prepared from Cp * ZrCl3 and BI3. Treatme nt of Cp ZrI3 with Li-2(THF)(C4H4BN(CHMe(2))(2)} yields Cp * (eta(5) -C4H4BN(CHMe(2))(2))ZrI . LiI(THF). Treatment of Cp (eta(5)-C4H4BN(C HMe(2))(2)MCl . LiCl (M = Zr, Hf) with allyl magnesium bromide yields Cp (eta(5)- C(4)Me(4)BN(CHMe(2))(2)}M(eta(3)-C3H5) (M = Zr, Hf). Add ition of donor ligands to Cp (eta(5)-C4H4BN(CHMe(2))(2))Hf(eta(3)-C3 H5) yields Cp (eta(5)-C4H4BN(CHMe(2))(2)}Hf(eta(3)-C3H5)(L) (L = PMe (3), CO) and Cp (eta(5)-C4H4BN(CHMe(2))(2)}Hf(eta(1)-C3H5)(py). The results of X-ray structure determinations for Cp (eta(5)-C4H4BN(CHMe (2))(2)Hf(eta(3)-C3H5) and Cp (eta(5)-C4H4BN(CHMe(2))(2)}Hf(eta(3)-C 3H5)(CO) are reported.