A 1D Schiff base zinc polymer as a versatile metallo-ligand for the synthesis of polynuclear zinc cages

Abstract

The 1D polymeric Schiff base zinc complex, [LZn₂Et₂]_n, where LH₂ = (NN′-ethylene-bis(4-iminopentan-2-one)) has been demonstrated as a useful synthetic metallo building block for the synthesis of homo and heteronuclear zinc cages. The reaction of [LZn₂Et₂]_n with CdI₂ afforded the hetero-nuclear cage, 1, [L₂Zn₄(Et)₂CdI₄], while reaction with HgI₂ afforded a hexanuclear zinc cage, [L₂Zn₆(Et)₄(μ₄O)(μ₃OEt)I], 2. The versatility of [LZn₂Et₂]_n as a metallo building block is demonstrated through the reaction with ferrocenyl carboxylic acid, affording the ferrocenyl supported zinc cage, [L₂Zn₈(FcCO₂)₄(Et)₂(OEt)₂(μ₄O)₂], 3, while the reaction with Er(III) acetate afforded the decanuclear zinc cage, [L₃Zn₁₀(μ₄O)₄(Et)₆], 4.