
Multiheteromacrocycles that complex metal ions. Second progress report, 1 May 1975--30 April 1976
Author(s) -
Donald J. Cram
Publication year - 1976
Language(s) - English
Resource type - Reports
DOI - 10.2172/4086876
Subject(s) - chemistry , metal , ligand (biochemistry) , crystallography , ion , stereochemistry , inorganic chemistry , medicinal chemistry , organic chemistry , biochemistry , receptor
Objective is to develop cyclic and polycyclic host organic compounds to complex and lipophilize metal ions. Macrorings were synthesized: (OCH$sub 2$ CH$sub 2$ O CH$sub 2$COCH$sub 2$ COCH$sub 2$)$sub 2$ and (OCH$sub 2$ CH$sub 2$ O CH$sub 2$ COCH$sub 2$ COCH$sub 2$)$sub 3$. The smaller ring complexes divalent metals 10$sup 1+9$ times better than the open-chain model CH$sub 3$ O CH$sub 2$ CO CH$sub 2$ COCH$sub 2$ O CH$sub 3$, and the order in which metal ions are complexed is Cu$sup 2+$, UO$sub 2$$sup 2+$ greater than Ni$sup 2+$ greater than Fe$sup 2+$, Co$sup 2+$, Zn$sup 2+$, Cd$sup 2+$ greater than Mn$sup 2+$. The UO$sub 2$$sup 2+$ and Cu$sup 2+$ complexes were isolated and characterized. The larger ring complexes trivalent metals 10/sup 0.9-1.7/ times better than the open- chain model compound, and the order is La$sup 3+$, Ce$sup 3+$ greater than Cr$sup 3+$. Five other macrocycles were also synthesized, and their binding constants with Na, K, NH$sub 4$, and Cs picrates were measured. Six compounds containing one macroring and two inward-pointing ArOH or ArOCH$sub 3$ groups were also prepared and tested for binding of Li, Na, K, Rb, and NH$sub 4$ picrates. Racemic compounds containing two binaphthyls and its sulfur analog were prepared. Cage-shaped multiheteromacrocycles containing ten O ligand sites or four S and six O ligand sites were prepared and the binding capability of the first compound for picrates studied. Two ring systems with phosphonate ester groups were also prepared. (DLC