Metal Ion Guest Responsive Benzoxazine Dimers and Inclusion Phenomena of Cyclic Derivatives

Abstract

A series of benzoxazine dimers (1–9),esterified benzoxazine dimers (10–18),and benzoxazine dimer based macrocyclic derivatives(19–22) are prepared. The metalion guest responsive properties of the benzoxazine dimersobtained are clarified by using Pedersen's technique.The ion extractions of the benzoxazine dimers are controlledby the bulkiness of the functional group at the aza position.The ones with cyclohexyl bulky groups at the aza position,7–9, are two times higher than thosewith methyl groups, 1–3. The extractionsare close to 100% for esterified dimers (10–18).For the macrocyclic derived dimers, the ether cyclic derivatives,21-22, interact with sodium, potassium and cesium ionsat stoichiometric ratios 2:1 and 1:1 depending on themetal species, as evidenced from 1H-NMR.