Syntheses, Structures, and Luminescent Properties of a Series of Coordination Compounds Based on (4-Carboxylphenyl) (4-(2′-Carboxylphenyl)benzyl) Ether and Different N-Donor Ligands

Fourteen novel coordination compounds based on (4-carboxylphenyl) (4-(2′-carboxylphenyl)­benzyl) ether (H₂L) and different N-donor ligands have been hydrothermally synthesized and structurally determined by single-crystal X-ray diffraction analyses, namely, [Zn₃(L)₃(biim-4)₂]·H₂O (<b>1</b>), [Cd­(L)­(H₂O)­(biim-4)_0.5] (<b>2</b>), [Zn­(L)­(BIE)] (<b>3</b>), [Co­(L)­(BIE)] (<b>4</b>), [Cd­(L)­(BIE)] (<b>5</b>), [Ni­(L)­(BIE)] (<b>6</b>), [Ni­(L)­(phen)]·H₂O (<b>7</b>), [Co­(L)­(phen)]·H₂O (<b>8</b>), [Co­(HL)₂(phen)₂]·3H₂O (<b>9</b>), [Cd­(L)­(H₂O)­(phen)] (<b>10</b>), [Co­(L)­(H₂O)­(phen)] (<b>11</b>), [Cd­(L)­(phen)₂] (<b>12</b>), [Pb­(L)] (<b>13</b>), and [Pb­(L)­(phen)]·H₂O (<b>14</b>), where biim-4 = 1,1′-(1,4-butanediyl)­bis­(imidazole), BIE = 2,2′-bis­(1H-imidazolyl)­ether, and phen = 1,10-phenanthroline. Compound <b>1</b> displays an unusual three-dimensional (3D) binodal (4,5)-connected net with a point symbol of (4³·6²·8)­(4⁵·5·6⁴). Compound <b>2</b> exhibits one-dimensional (1D) looplike chain structures, which are further extended into a 3D supramolecular architecture through π–π interactions. Compounds <b>3</b>–<b>6</b> are isomorphous and feature similar two-dimensional (2D) layer structures. Compounds <b>7</b> and <b>8</b> are isomorphous and show the same zero-dimensional (0D) structures, which are further extended by π–π interactions into 2D supramolecular layers. Compound <b>9</b> displays a discrete [Co₂(L)₂(phen)₂] dimer. Neighboring dimers are further linked by π–π interactions to form a 1D double chain. Compounds <b>10</b> and <b>11</b> exhibit similar 1D double chain structures. The chains are further linked via π–π interactions to generate 2D supramolecular layers. Compound <b>12</b> shows a discrete [Cd₂(L)₂(phen)₂] dimer. The π–π stacking and hydrogen-bonding interactions further extend the dimers into a 3D supramolecular architecture. Compound <b>13</b> displays a typical (4⁴)-<b>sql</b> network structure. Neighboring networks are further linked by the π–π interactions, leading to an unusual 3D supramolecular architecture. Compound <b>14</b> exhibits a discrete [Pb₂(L)₂(phen)₂] dimer. Neighboring dimers are further linked by the π–π interactions to form a 2D supramolecular layer. The thermal stabilities and luminescent properties of the complexes have also been investigated in detail