Synthesis and structures of dinuclear cryptates with Zn( ii ), Cd( ii ) and Hg( ii ): tuning the cascade binding mode with metal ions

• Published in: CrystEngComm Vol. 17; no. 30; pp. 5832 - 5840
• Main Authors: Yan, Feng, Zhuang, Xiao-Mei, Lu, Tong-Bu
• Format: Journal Article
• Language: English
• Published: 01.01.2015
• Subjects: Anions; Binding; Cascades; Crystal structure; Mathematical analysis; Metal ions; Recognition; Tuning
• ISSN: 1466-8033; 1466-8033
• DOI: 10.1039/C5CE00817D

The crystal structures of eight cascade complexes, [Zn sub(2)L( mu -Cl)](ClO sub(4)) sub(3).2H sub(2)O.3CH sub(3)CN (1), [Zn sub(2)L( mu -Br)](ClO sub(4)) sub(3).2H sub(2)O.3CH sub(3)CN (2), [Cd sub(2)L( mu -OH)] sub(2)[ CdI sub(4)] sub(3).6DMF (3), [Cd sub(2)L( mu -Cl)][CdCl sub(4)](Cl).4.5H sub(2)O (5), [Cd sub(2)L( mu -Br)][CdBr sub(4)](Br).1.5H sub(2)O (6), [Hg sub(2)L( mu -Cl)][HgCl sub(4)](Cl).6H sub(2)O (9), [Hg sub(2)L( mu -Br)][HgBr sub(4)](Br).1.25H sub(2)O (10), and [Hg sub(2)L( mu -I)](NO sub(3)) sub(3).6H sub(2)O (11), were presented, which reveal the influence of the coordinated metal ions on the selectivity in the cascade binding mode. The dizinc(ii) cryptate shows the recognition of Cl super(-) and Br super(-) rather than that of F super(-) and I super(-). Unexpectedly, the dicadmium(ii) cryptate shows the recognition of OH super(-), F super(-), Cl super(-) and Br super(-) rather than that of I super(-), while all of the above-mentioned anions can form stable cascade complexes with the dimercury(ii) cryptate. For better understanding, the binding behaviors and stabilisation energies between [M sub(2)L] super(4+) and anions were calculated by DFT calculations.