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Paper | Regular issue | Vol 26, No. 4, 1987, pp.989-1000
Published online, 1st January, 1970
DOI: 10.3987/R-1987-04-0989
Proton-ionizable Macrocycles Containing 1,2,4-Triazole and 4-Amino-1,2,4-triazole Subunits

José M. Alonso, M. Rosario Martín, Javier de Mendoza, Tomás Torres, and José Elguero

*Departamento de Química Orgánica, Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco, 28049-Madrid, Spain

Abstract

Macrocycles 2a and 2b, containing a proton-ionizable 1,2,4-triazole subcyclic unit, havebeen obtained from the appropriate 3,5-disubstituted N-amino-1,2,4-triazoles and tetraethyleneglycol derivatives. The N-amino function was used as a protective group in the macrocyclization step. The method allowed the preparation of the chiral macrocycle 2b in three steps, from S-lactic acid, in high optical purity and an overall yield of 16%. Triazolyl lone pairs of the macrocycles 2a and 2b, and of their N-aminated precursors 1a and 1b, participate in the complexation of Eu(fod)3 and Pr(fod)3, as well as the crown ether moieties, but not N-amino groups which, when present, were found to be inside the cavity. Ion transport rates towards alkali-metal ions through a bulky chloroform phase were low and showed little selectivity.