Crystal structure, shape analysis and bioactivity of new LiI, NaI and MgII complexes with 1,10-phenanthroline and 2-(3,4-dichlorophenyl)acetic acid

Abstract

Reactions of 1,10-phenanthroline (phen) and 2-(3,4-dichlorophenyl)acetic acid (dcaH) with Mn (CO3) (M = LiI, NaI and MgII; n = 1 and 2) in MeOH yield the mononuclear lithium complex aqua[2-(3,4-dichlorophenyl)acetato-κO](1,10-phenanthroline-κ2 N,N′)lithium(I), [Li(C8H5Cl2O2)(C12H8N2)(H2O)] or [Li(dca)(phen)(H2O)] (1), the dinuclear sodium complex di-μ-aqua-bis{[2-(3,4-dichlorophenyl)acetato-κO](1,10-phenanthroline-κ2 N,N′)sodium(I)}, [Na2(C8H5Cl2O2)2(C12H8N2)2(H2O)2] or [Na2(dca)2(phen)2(H2O)2] (2), and the one-dimensional chain magnesium complex catena-poly[[[diaqua(1,10-phenanthroline-κ2 N,N′)magnesium]-μ-2-(3,4-dichlorophenyl)acetato-κ2 O:O′] 2-(3,4-dichlorophenyl)acetate monohydrate], {[Mg(C8H5Cl2O2)(C12H8N2)(H2O)2](C8H5Cl2O2)·H2O} n or {[Mg(dca)(phen)(H2O)2](dca)·H2O} n (3). In these complexes, phen binds via an N,N′-chelate pocket, while the deprotonated dca− ligands coordinate either in a monodentate (in 1 and 2) or bidentate (in 3) fashion. The remaining coordination sites around the metal ions are occupied by water molecules in all three complexes. Complex 1 crystallizes in the triclinic space group P\overline{1} with one molecule in the asymmetric unit. The Li+ ion adopts a four-coordinated distorted seesaw geometry comprising an [N2O2] donor set. Complex 2 crystallizes in the triclinic space group P\overline{1} with half a molecule in the asymmetric unit, in which the Na+ ion adopts a five-coordinated distorted spherical square-pyramidal geometry, with an [N2O3] donor set. Complex 3 crystallizes in the orthorhombic space group P212121, with one Mg2+ ion, one phen ligand, two dca− ligands and three water molecules in the asymmetric unit. Both dcaH ligands are deprotonated, however, one dca− anion is not coordinated, whereas the second dca− anion coordinates in a bidentate fashion bridging two Mg2+ ions, resulting in a one-dimensional chain structure for 3. The Mg2+ ion adopts a distorted octahedral geometry, with an [N2O4] donor set. Complexes 1–3 were evaluated against urease and α-glucosidase enzymes for their inhibition potential and were found to be inactive.