A New Mode of Metal Encapsulation (pages 1404–1406)
Dr. John S. Bartlett, James F. Costello, Dr. Shrock Mehani, Dr. S. Ramdas, Alexandra M. Z. Slawin, Dr. J. Fraser Stoddart and Dr. David J. Williams
Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199014041
All ten oxygen atoms of the acyclic oligomer 1 c participate in the coordination of Ba2⊕ in the “scorpion” complex 1c · Ba(SCN)2 · Me2CO. The eleventh coordination site is occupied by the acetone molecule. A further characteristic of the complex are strong OHċN hydrogen bonds to the thiocyanate counterion. The ligands 1 also exhibit a high selectivity for cations with ionic radii of 1.2–1.3 Å, which could be explained with the help of molecular modeling studies.