Synthesis and Structural Characterization of β-Diketoiminate Complexes Containing Three-Coordinate Zinc and Copper Atoms

Abstract

The reaction of the lithium β-diketoiminate complex (dipp)NacNacLi·OEt2 {(dipp)NacNac = 2-[(2,6-diisopropylphenyl)amino]-4-[(2,6-diisopropylphenyl)imino]pent-2-enyl} with ZnCl2 yielded the corresponding (dipp)NacNacZnCl (1) and (dipp)NacNacZn(μ-Cl)2Li(OEt2)2 (1a). Treatment of 1 with LiC≡CPh and NaBH4 in diethyl ether gave (dipp)NacNacZnC≡CPh (2) and (dipp)NacNacZn(μ-H)2BH2 (3). The core element of compounds 1a−3 is a six-membered ZnN2C3 ring. The structure of 1a shows the β-diketoiminate backbone in a boat conformation with the tetrahedrally coordinated metal centre in 1a at the prow and the opposing carbon atom at the stern. The zinc atoms in 2 and 3 show a planar arrangement to the β-diketoiminate plane. The zinc atom in 2 is three-coordinated and that in 3 four-coordinated. Treatment of (dipp)NacNacLi·OEt2 with CuI in diethyl ether yielded {[Li(OEt2)][(dipp)NacNacCuI]}2 (4). In contrast to 1a−3, compound 4 contains a dimetallic system. The core of compound 4 consists of two six-membered LiN2C3 rings and one four-membered Cu2I2 ring. In addition to bonds to the two iodine atoms, the three-coordinated copper atom has a further bond to the γ-carbon atom of the six-membered LiN2C3 ring. (© Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002)