Syntheses, Structures, and Properties of Three Metal‐Organic Complexes with Different Dimensionality Based on Dipyrido[3,2‐d:2′3′‐f]quinoxaline and Different Dicarboxylates

Three new metal‐organic complexes [Ni 2 (dpq) 2 (L 1 ) 2 (H 2 O) 5 ] · H 2 O ( 1 ), [Pb 2 (dpq) 2 (L 1 ) 2 ] · H 2 O ( 2 ), and [Pb(dpq)(L 2 )] ( 3 ) (dpq = dipyrido[3,2‐d:2′3′‐f]quinoxaline, H 2 L 1 = 1,1′‐biphenyl‐2, 2′‐dicarboxylic acid, H 2 L 2 = 2‐carboxymethylsulfanyl nicotinic acid) were synthesized under hydrothermal conditions and structurally characterized by elemental analyses, IR, and single‐crystal X‐ray diffraction analyses. X‐ray analysis reveals that complex 1 has a semi‐cycling dinuclear unit, which is extended into a 3D supramolecular architecture by hydrogen bonding and π–π stacking interactions. Complex 2 is an unusual 0D + 1D cocrystal of dinuclear units and left‐/right‐handed helical chains, which are ultimately packed into a 3D supramolecular structure through hydrogen bonding interactions. Complex 3 shows a 2D network bridged by L 2 anions, which is finally extended into a 3D supramolecular structure through π–π stacking interactions. The diverse structures of complexes 1 – 3 indicate that the central metal ions and the dicarboxylates have significant effects on the final structures. Moreover, the thermal stabilities, the photoluminescent properties of complexes 1 – 3 and the electrochemical property of complex 1 were also investigated.