Structure-directing role of the asymmetric methyl-4-(pyrimidin-2-ylcarbamoyl)benzoate ligand in the self-assembly of Co(II), Ni(II), Cu(II) and Cu(I) complexes

The reactions of methyl-4-(pyrimidin-2-ylcarbamoyl)benzoate (L) with Co(II), Ni(II), Cu(II) and Cu(I) metal salts afforded [Co(L)2(CH3OH)2](ClO4)2 (1), [Co(L)2(CH3OH)2](BF4)2 (2), [Ni(L)2(CH3OH)2](BF4)2 (3), [Cu(L)2(ClO4)2]·2CH3OH (4), [Cu(L)2(BF4)2]·2CH3OH (5), [Cu(L)2Br2]·CH3OH (6), [Cu2(L)Cl4·CH3CN]∞ (7), [Cu3.5(L)Br4·0.5C2H5OC2H5]∞ (8) and [Cu2(L)I2]∞ (9), which have been structurally characterized by X-ray crystallography. Four types of ligand conformation-coordination mode, cis-bidentate, cis-tridentate, trans-bidentate and trans-tridentate, are observed for the L ligand in these complexes, resulting in mononuclear structures for 1–6, layer structures for 7 and 8 and a chain structure for 9. C–H⋯π and π⋯π interactions and various hydrogen bonds are found in these complexes that extend the dimensionalities of the structures, and the structural types of the copper halide aggregates in 7–9 are unique.

Graphical abstractFour types of ligand conformation-coordination mode, cis-bidentate, cis-tridentate, trans-bidentate and trans-tridentate, are observed for the methyl-4-(pyrimidin-2-ylcarbamoyl)benzoate (L) ligand in nine Co(II), Ni(II), Cu(II) and Cu(I) metal complexes, resulting in mononuclear structures for 1–6, 2D layers for 7 and 8 and a 1D chain for 9. C–H⋯π and π⋯π interactions and various hydrogen bonds are found in these complexes which extend the dimensionalities of the structures, and the structural types of the copper halide aggregates in 7–9 are unique.Figure optionsDownload full-size imageDownload as PowerPoint slide