Four binuclear coordination polymers with a 63 net and self-assembly of 2D 63 topology into different supramolecular networks using unit–unit H-bonds†
Abstract
In this work, crystal engineering is focused on the self-assembly of 2D 63 topology into different supramolecular networks using unit–unit H-bonds. Four related coordination polymers, [Zn2(teaH2)(ndc)1.5]·MeOH (1), [Co2(teaH2)(ndc)1.5]·MeOH (2), [Zn2(deaH)(ndc)1.5]·MeOH (3) and [Co2(teaH2)(btb)]·3EtOH (4) where ndc2− = 2,6-naphthalenedicarboxylate, btb3− = benzene-1,3,5-tribenzoate, teaH3 = triethanolamine, and deaH2 = diethanolamine, contain a well-known 63 subnet and the binuclear units. Furthermore, their 63 nets present different hexagonal windows (chair- or ship-shaped) and diversified layer arrays (ABAB or ABCABC sequence). The 63 subnet and symmetry-related unit–unit H-bonds as supramolecular synthons can build up different supramolecular networks. Compounds 1 and 2 show a distorted diamond supramolecular network due to formation of a square-pyramidal node. Because the formation of a seesaw-shaped node, compound 3 features a general diamond supramolecular network with 3-fold interpenetration. Compound 4 exhibits a binodal supramolecular framework in that H-bonding interactions occur between three binuclear units. In addition, the diversified layer array has endowed compound 4 with a large 1D channel, which can be characterized by standard N2 adsorptions. Compound 4 has a type I adsorption isotherm with an appreciable adsorption of 45.04 cm3 g−1 at 0.40 P/P0, whereas 1–3 do not exhibit appreciable N2 uptake.