Chemoselective Deprotonations of a Cationic Zirconium Primary Amido Complex to Either a Neutral Zirconium Terminal Imido or a Noninterconverting Tautomer

Chemoselective deprotonation of {Cp*Zr(NH<sup>t</sup>Bu)[N(<sup>i</sup>Pr)C(Me)N(<sup>i</sup>Pr)]}[B(C<sub>6</sub>F<sub>5</sub>)<sub>4</sub>] (<b>2a</b>) cleanly provides either the neutral enolamide, Cp*Zr(NH<sup>t</sup>Bu)[N(<sup>i</sup>Pr)C(CH<sub>2</sub>)N(<sup>i</sup>Pr)] (<b>5</b>), or the terminal imido, Cp*Zr(N<sup>t</sup>Bu)[N(<sup>i</sup>Pr)C(CH<sub>3</sub>)N(<sup>i</sup>Pr)] (<b>6</b>). These two tautomers do not interconvert, and no evidence was obtained for deprotonation of <b>2a</b> in the presence of an excess of the primary amine <sup>t</sup>BuNH<sub>2</sub>.