Effect of a catechol segment in a polyether chain on the complexing ability of some phosphonate and quinoline monopodands

The complexing ability of monopodands with o-diethoxyphosphinylmethoxyphenyl and 8-quinoline end groups, containing both ethylene glycol and catechol units in the polyether chain, was studied by conductimetry in tetrahydrofuran-CHCl3. Replacement of ethvlene glycol by catechol changes the efficiency insignificantly, but in a number of cases leads to some increase in K/Li and k/Na selectivity of phosphonate podands, and the K/Li and Na/Li selectivity of quinoline podands.