Rogers, Robin D.
B.S. (Bachelor of Science)
Department of Chemistry and Biochemistry
In my senior honors research project, the study of neutral solvent/crown ether interactions and f-element/crown ether complexes, I have been investigating the conditions under which water molecules may be excluded from a late lanthanide ion's primary coordination sphere by complexation of a crown ether ligand. Our group has found water molecules to be strongly retained when using hydrated f-element salts. When the chloride ion is utilized, as in much of our current work, the water molecules stabilize the metal ion by coordination, the chloride ions by hydrogen bonding, and they hydrogen bond the crown ether, as in [M(OH₂)₈]Cl₃·15-crown-5 (M = Y, Cd, Lu), [Dy(OH₂)₈]Cl₃·18-crown-6·4H₂O, and [Lu(OH₂)₈]Cl₃·1.5(12-crown-4) 2H₂O. Even when the crown ether complexes the metal ion, some water molecules are usually retained as in [MCl(OH₂)₂(18-crown-6)]Cl₂·2H₂O (M = Sm, Gd, Tb) and [M(OH₂)₇(OHMe)][MCl(OH₂)₂(18-crown-6)]₂Cl₇·2(H₂O) (M = Y, Dy). Recently we have isolated anhydrous triethylene glycol derivatives of MCl₃ nH₂O: MCl₃(triethylene glycol)18-crown-6 (M = Y, Dy). Further study with the glycol alone yielded crystals of [M(OH₂)₅(triethylene glycol)]Cl₃ (M = Y, Dy, Gd). This paper will present the synthesis and structures of these complexes and discuss their possible utility in the preparation of anhydrous f-element/crown ether complexes.
Voss, Eric John, "Synthetic and structural investigations of neutral solvent/crown ether interactions and f-element/crown ether complexation" (1987). Honors Capstones. 1083.
ii, 58 pages
Northern Illinois University
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