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N-Tosylpyrrolidine calix[4]pyrrole: synthesis and ion binding studies.

ABSTRACT: The synthesis and preliminary solution phase ion binding properties of the N-tosylpyrrolidine calix[4]pyrrole 2 are reported. This ?-octaalkyl-substituted calix[4]pyrrole, the first to be prepared via a direct condensation reaction, was obtained by reacting the 3,4-alkyl-functionalized pyrrole 8 with acetone in the presence of an acid catalyst. On the basis of (1)H NMR spectroscopic analyses and isothermal titration calorimetry, it was concluded that, compared with the parent, ?-unsubstituted calix[4]pyrrole (1), compound 2 possesses significantly enhanced binding ability for halide anions in chloroform. Furthermore, 2 proved capable of solubilizing in chloroform solution the otherwise insoluble salts, CsF and CsCl. These effects are ascribed to the interactions between the four tosyl groups present in 2 and the counter cations of the halide anion salts.

SUBMITTER: Kim SK

PROVIDER: S-EPMC3134555 | biostudies-literature | 2011 Feb

REPOSITORIES: biostudies-literature

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N-Tosylpyrrolidine calix[4]pyrrole: synthesis and ion binding studies.

Kim Sung Kuk SK Gross Dustin E DE Cho Dong-Gyu DG Lynch Vincent M VM Sessler Jonathan L JL

The Journal of organic chemistry 20101209 4

The synthesis and preliminary solution phase ion binding properties of the N-tosylpyrrolidine calix[4]pyrrole 2 are reported. This β-octaalkyl-substituted calix[4]pyrrole, the first to be prepared via a direct condensation reaction, was obtained by reacting the 3,4-alkyl-functionalized pyrrole 8 with acetone in the presence of an acid catalyst. On the basis of (1)H NMR spectroscopic analyses and isothermal titration calorimetry, it was concluded that, compared with the parent, β-unsubstituted ca ...[more]

PMID: 21141913

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