The complexing behavior of 1,1 " :1 ' ,1 ' ' ' -bis(1,4,10,13-tetraoxa-7,16
-diazacyclooctadecane-7,16-diyldimethyl)bisferrocene (I) toward KPF6 ion wa
s studied. To gain a better understanding into the factors which determine
the extent of this redox-switched bonding in the complexation of KPF6 by 1,
we carried out X-ray crystal structural determination, NMR, FAB-MS techniq
ue, cyclic voltammetry measurements, and Fe-57 Mossbauer analyses. We sugge
st that the KPF6 salt of 1 is not a kinetically labile system. Our studies
also provide direct evidence that ferrocene crown ether displays a drop in
complex stability upon oxidation. (C) 2001 Elsevier Science B.V. All rights
reserved.