Di-ionizable p-tert-butylcalix[4]arene-1,3-crown-4 ligands: synthesis and alkaline earth metal cation extraction
作者:Xiaodong Liu、Kazimierz Surowiec、Richard A. Bartsch
DOI:10.1016/j.tet.2009.06.004
日期:2009.8
synthesized. The ionizable groups are oxyacetic acid and N-(X)sulfonyl oxyacetamide groups with X=methyl, phenyl, 4-nitrophenyl and trifluoromethyl, which ‘tunes’ the acidity of the latter. The efficiency and selectivity of these novel ligands are assessed with competitivesolventextractions of alkalineearth metal cations from aqueous solutions into chloroform. The results are compared with those reported