Facile Syntheses of Dibenzo-14-crown-41a and bis-butylbenzo-14-crown-41b

Abstract Although there is a wide interest in the syntheses of macrocyclic compounds, since Pedersen's2 and Lehn's3 introduction that they are capable of forming stable complexes with the alkali ions, only few attentions have been given to utilize crown-4 as complexing agents.4–7 However, the unsubstituted 12-crown-41c appeared to be a good complexing agent which forms a 1:1 complex with lithium cation.6,7 Recently, we were interested in the synthesis of dibenzo-14-crown-4 with alkyl substituents on benzo groups and utilizing it as an extracting agent for selectively extracting lithium cation from aqueous solution.8