Hafnium dichloride species

In the case of zirconium and hafnium the lack of accessible dichlorides means that alkyl derivatives are generated via the corresponding homoleptic alkyl intermediates. With bulky 2,6-di-ferf-butylphenoxide the tris-benzyls [(ArO)ZrR3] can be isolated and studied. " The dialkyls [(ArO)2MR2] (M = Zr, Hf R = Me, benzyl) can also be isolated for bulky aryloxides. In the case of 2,6-diphenylphenols the monomethyl species [(ArO)3ZrMe] are readily formed by simple addition of parent phenol to the dimethyl compound. 

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