Supramolecular Organic Frameworks of Brominated Bisphenol Derivatives with Organoamines

Reactions of two brominated bisphenol derivatives, tetrabromobisphenol-F (TBBPF) and tetrabromobisphenol-A (TBBPA), with various organoamines resulted in six supramolecular organic frameworks (SOFs), formulated as (TBBPF^2–)₂·(HPZ⁺)₂·(H₂PZ²⁺) (1), (TBBPF^–)₂·(H₂PZ²⁺)·2H₂O·2MeOH (2), (TBBPF)·(TBBPF^–)·(HDABCO⁺)·H₂O (3), (TBBPF)·(HMTA) (4), (TBBPA)·(HMTA) (5), and (TBBPA)₃·(HMTA)₃·H₂O (6) (PZ = piperazine; DABCO = diazabicyclo[2.2.2]octane; HMTA = hexamethylenetetramine). Compounds 1–6 were characterized by single-crystal and powder X-ray diffractions. The predominant driving forces in 1–6 are hydrogen bonds (H-bonds), by which the compounds assemble into supramolecular organic frameworks with versatile topological structures. Compound 1 contains TBBPF/PZ in a 2:3 ratio and exhibits 2D (two-dimensional) H-bonded supramolecular 4⁴-sql layer structure built by the four-connected {H₂PZ²⁺} moieties and {TBBPF^2–}. Compound 2 shows a 2-fold interpenetrated 3D (three-dimensional) H-bonded networks comprised by TBBPF/PZ in 2:1 ratio with the presence of solvent H₂O and MeOH molecules, in which two identical pcu topological nets are recognized by choosing a decamer synthons as nodes. Compound 3 displays H-bonded 4⁴-sql layer structure built by 2:1 TBBPF and DABCO, as well as one H₂O per formula unit. Compounds 4 and 5 assemble into 1D (one-dimensional) H-bonded zigzag chains via the alternate linkage of HMTA with TBBPF/TBBPA in a similar fashion. Compound 6 generates an interesting hexamer subunit (HMTA···TBBPA···HMTA···TBBPA···HMTA···TBBPA), which can be viewed as a fragment of three repeating units for a zigzag chain observed in compound 5. A pair of the hexamer subunits is further connected by two water molecules to form an H-bonded molecular oligomer. Importantly, halogen bonds (X-bonds) have been observed in compounds 4–6 that exhibit 1D and 0D H-bonded supramolecular structures.