The syntheses and free energies of association of 12 new macrocyclic ligand systems (hosts) with alkali metal and ammonium and alkylammonium picrates in CdCl/sub 3/ are reported at 25/sup 0/C. Ten of the hosts were composed of 4-methylanisole units (abbreviated AN) incorporated into the macroring by substitution at their 2,6 positions by CH/sub 2/O(MO) units, or by direct attachment to other AN units at their 2,6 positions. The macrorings were completed with CH/sub 2/CH/sub 2/ (E) units and additional ether oxygens (O). The other two ligand systems were (AN/sub 2/DP(OEOEO)/sub 2/E (39) and DP(OEOEO)/sub 2/E (40), in which DP = 5,5'-dimethyldiphenyl substituted in the 2,2' positions with O and the 3,3' positions with either H or 2-methoxy-5-methylphenyl (AN) groups. These systems were compared with model macrocyclic ethers not containing anisole units. General ion selectivity of each ligand system was measured by the difference in free energies between the best and poorest bound of the picrate salts, -..delta..(..delta..G/sub max/) (kcal/mol). These results demonstrate that, when the oxygens of anisole units are held in sterically enforced conformations which make the unshared electron pairs provide the lining of partially spherical cavities, the anisole units become better and more selective complexers of anions thanmore » the now classic crown ether compounds. Such conformations are observed only when m-teranisyl units are incorporated in macroring systems. 3 tables.« less