Divalent metal succinate/perchlorate coordination polymers incorporating a kinked hydrogen-bonding capable diimine: Chains, layers and a (5,6)-connected binodal network featuring alternating rectangular and hexagonal grids

Hydrothermal synthesis has afforded succinate (suc) or 2,2-dimethylsuccinate (dmsuc) perchlorate coordination polymers with divergent dimensionality incorporating the kinked hydrogen-bonding capable diimine tethering ligand 4,4′-dipyridylamine (dpa): {[Co(suc)(Hdpa)2(H2O)2](ClO4)2 · 7.5H2O}n (1), {[Cd3(suc)2.5(dpa)2](ClO4)}n (2) and {[Cd2(dmsuc)2(dpa)(Hdpa)](ClO4) · 6H2O}n (3). Influenced by coordination geometry preferences, compound 1 manifests simple cationic one-dimensional (1D) [Co(suc)(Hdpa)2(H2O)2]n2n+ polymeric chains, while 2 possesses a unique three-dimensional (3D) binodal (5,6)-connected (4664)(41065) network. The network of 2 can also be viewed as alternating (4,4) rectangular and (6,3) hexagonal grids being joined by pillaring ligands. The steric bulk imparted by the gem-dimethyl substituents within the dmsuc ligands results in a two-dimensional (2D) (6,3) herringbone net in 3. The d10 derivatives 2 and 3 undergo blue–violet luminescence upon exposure to ultraviolet radiation.

Graphical abstractHydrothermal synthesis has afforded succinate (suc) or 2,2-dimethylsuccinate (dmsuc) perchlorate coordination polymers incorporating the hydrogen-bonding capable tethering ligand 4,4′-dipyridylamine (dpa). {[Co(suc)(Hdpa)2(H2O)2](ClO4)2 · 7.5H2O}n (1) manifests simple cationic 1D polymeric chains, while {[Cd3(suc)2.5(dpa)2](ClO4)}n (2) possesses a 3D binodal (5,6)-connected network. The network of 2 can be viewed as alternating (4,4) rectangular and (6,3) hexagonal grids being joined by pillaring ligands. The gem-dimethyl substituents within the dmsuc ligands promote a 2D (6,3) herringbone net in {[Cd2(dmsuc)2(dpa)(Hdpa)](ClO4) · 6H2O}n (3).Figure optionsDownload full-size imageDownload as PowerPoint slide