Homochiral Metal−Organic Frameworks Based on Transition Metal Bisphosphonates

• Published in: Chemistry of materials 2002-09, Vol.14 (9), p.3866-3874
• Main Authors: Evans, Owen R, Manke, David R, Lin, Wenbin
• Format: Article
• Language: English
• Subjects: Chemistry; Condensed matter: structure, mechanical and thermal properties; Coordination compounds; Exact sciences and technology; Inorganic chemistry and origins of life; Inorganic compounds; Metal complexes; Physics; Preparations and properties; Structure of solids and liquids; crystallography; Structure of specific crystalline solids
• ISSN: 0897-4756; 1520-5002
• DOI: 10.1021/cm0202714

Homochiral metal−organic frameworks with binaphthylbisphosphonate bridging ligands [Mn(L-H2)(MeOH)]·(MeOH), 1, [Co2(L-H2)2(H2O)3]·(H2O)4, 2, [Ni(L-H2)(MeOH)4], 3, [Cu(L-Et2)], 4, and [Zn3(L-H)2(C6H5N)2], 5, where L is completely deprotonated enantiopure 2,2‘-diethoxy-1,1‘-binaphthalene-6,6‘-bisphosphonic acid, were synthesized under hydro(solvo)thermal reactions. Single-crystal X-ray diffraction studies reveal that 3−5 adopt condensed network structures, while compounds 1 and 2 adopt robust three-dimensional open-framework structures possessing rhombohedral channels. Solid-state circular dichroism spectra indicate that compounds 1−5 made from bridging ligands of opposite handness are supramolecular enantiomers. Compounds 1, 5, and L-H4 exhibit strong blue fluorescence in solid state, and the formation of excimers in 5 and L-H4 in solid state correlates well with the π−π stacking interactions. The present work illustrates the potential of rational synthesis of robust chiral porous network solids. The chiral pockets and functionalities within crystalline chiral porous solids may find important applications in enantioselective processes.