Zinc Pyrazolylborate Complexes with Phenoxide and Alkoxide Ligands

The zinc hydroxide complexes Tp*Zn‐OH of highly substituted pyrazolylborate ligands react with phenols, and alcohols, of sufficient acidity, in a condensation reaction with release of H 2 O. Starting with phenols the following were attached:phenolate, p ‐nitropehnolate, o ‐vanillinate, o ‐hydroxymethylphenolate, o , o ‐bis(hydroxymethyl) ‐ p ‐methylphenolate. Whilst aliphatic alcohols and benzyl alcohol did not react, their derivatives, with highly electronegative substituents could be incorporated. Thus, the arylmethoxides OCH 2 C 6 F 5 and OCH 2 C 6 H 4 NO 2 ‐ p , as well as the alkoxides OCH 2 CF 3 and OCH 2 CCl 3 , were attached. 2‐Mercaptoethanol was bound via its thiolate function. The crystal structures of Tp Cum,Me ZN‐OC 6 H 4 NO 2 ‐ p ,Tp Cum,Me ZN‐OCH 2 ‐C 6 F 5 , Tp Cum,Me ZN‐OCH 2 CF 3 , Tp Cum,Me ZN‐OCH 2 CCl 3 and Tp Cum,Me Zn‐SCH 2 CH 2 OH were determined.