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Conversion Between Doubly and Triply Carboxylate-Bridged Di(ethylzinc) Complexes and Formation of the (μ-Oxo)tetrazinc Carboxylate [Zn₄O(Ar^TolCO₂)₆].

ABSTRACT: Ethylzinc 2,6-bis(p-tolyl)benzoate converts between two forms in solution. Through NMR spectroscopic techniques and X-ray crystallography, the species in equilibrium were identified as [Zn₂(Ar^TolCO₂)₂(Et)₂(THF)₂] (1), [Zn₂(Ar^TolCO₂)₃(Et)(THF)] (2), and diethyl zinc (Ar^Tol = 2,6-bis(p-tolyl)phenyl). The equilibrium provides a model for understanding the speciation between doubly and triply m-terphenylcarboxylate-bridged diiron(II) and mononuclear iron(II) complexes. Evidence is presented for the occurrence of coordinatively unsaturated trigonal zinc species in solution. Both 1 and 2 decompose in air to form the T-symmetric oxozinc carboxylate, [Zn₄O(Ar^TolCO₂)₆] (3).

SUBMITTER: Minier MA

PROVIDER: S-EPMC3994167 | biostudies-literature |

REPOSITORIES: biostudies-literature

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