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Selective Anion Extraction and Recovery Using a Fe^II₄ L₄ Cage.

ABSTRACT: Selective anion extraction is useful for the recovery and purification of valuable chemicals, and in the removal of pollutants from the environment. Here we report that Fe^II₄ L₄ cage 1 is able to extract an equimolar amount of ReO₄^- , a high-value anion and a nonradioactive surrogate of TcO₄^- , from water into nitromethane. Importantly, the extraction was efficiently performed even in the presence of 10 other common anions in water, highlighting the high selectivity of 1 for ReO₄^- . The extracted guest could be released into water as the cage disassembled in ethyl acetate, and then 1 could be recycled by switching the solvent to acetonitrile. The versatile solubility of the cage also enabled complete extraction of ReO₄^- (as the tetrabutylammonium salt) from an organic phase into water by using the sulfate salt of 1 as the extractant.

SUBMITTER: Zhang D

PROVIDER: S-EPMC6001518 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature

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Selective Anion Extraction and Recovery Using a FeII4 L4 Cage.

Zhang Dawei D Ronson Tanya K TK Mosquera Jesús J Martinez Alexandre A Nitschke Jonathan R JR

Angewandte Chemie (International ed. in English) 20180223 14

Selective anion extraction is useful for the recovery and purification of valuable chemicals, and in the removal of pollutants from the environment. Here we report that FeII4 L4 cage 1 is able to extract an equimolar amount of ReO4- , a high-value anion and a nonradioactive surrogate of TcO4- , from water into nitromethane. Importantly, the extraction was efficiently performed even in the presence of 10 other common ani ...[more]

PMID: 29393989

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