Group 4 Zwitterionic Metallocenes Based upon the Bridged Amido-Cyclopentadienyl Ligand and Coordinated Dienes

The reaction of (η5-C5Me4SiMe2NtBu)Zr(1,3-pentadiene) with B(C6F5)3 results in the formation of the zirconium
borate zwitterion complex (η5-C5Me4SiMe2NtBu)Zr(η3-CH3(CH)3CH2B(C6F5)3) (1). Furthermore, reaction of (η5-C5Me4SiMe2NtBu)Ti(2,4-hexadiene), (η5-C5Me4SiMe2NtBu)Ti(2-methyl-1,3-butadiene), (η5-C5Me4SiMe2NtBu)Ti(1,3-butadiene), and (η5-C5Me4SiMe2NtBu)Ti(2,3-dimethylbutadiene) with either B(C6F5)3 or Al(C6F5)3 results
in the formation of (η5-C5Me4SiMe2NtBu)Ti(η3-CH3CH2(CH)3CH2B(C6F5)3) (2), (η5-C5Me4SiMe2NtBu)Ti(η3-CH2C(CH3)CHCH2Al(C6F5)3) (3), (η5-C5Me4SiMe2NtBu)Ti(η3-CH2(CH)2CH2B(C6F5)3) (4), and (η5-C5Me4SiMe2NtBu)Ti(η3-CH2C(CH3)C(CH3)CH2B(C6F5)3) (5). The X-ray crystal structures of 1−4 have been determined.