Synthesis and crystal structure of a new lapacholate complex with nickel(II), [Ni(Lap)₂(DMF)(H₂O)]

Abstract

The crystal and molecular structure of dilapacholateaqua(dimethylformamide)nickel(II) was determined by X-ray diffraction. It crystallizes in the triclinic space group P 1 with a = 9.8671(9) Å, b = 10.654(1) Å, c = 15.289(2) Å, α = 86.98(1)°, β = 79.32(1)°, γ = 87.031(8)°, and Z = two molecules per unit cell. The structure was solved from 5094 reflections with I>2σ(I) and refined by full matrix least-square to an agreement R ₁-factor of 0.0564. The nickel(II) is in a NiO₆ octahedral environment, cis coordinated to two lapacholate anions through their adjacent carbonyl [Ni–O distances of 2.075(2) and 2.066(2) Å], and phenyl oxygens [Ni–O lengths of 2.011(2) and 2.021(2) Å], and to a water [d(Ni–Ow) = 2.073(2) Å] and a DMF [d(Ni–O) = 2.076(2) Å] at axial positions. Some physicochemical and spectroscopic properties of the complex are also reported.

Keywords:

• Lapacholate
• Ni(II) complex
• Crystal structure
• Spectroscopic properties

Acknowledgments

We thank Prof M. Poch of the Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Argentina, for providing us with the LapH samples. The X-ray diffraction data were collected at LANADI (CONICET). O.E. Piro is a Research Fellow of CONICET.