Journal
CHEMISTRY-A EUROPEAN JOURNAL
Volume 17, Issue 25, Pages 7020-7031Publisher
WILEY-V C H VERLAG GMBH
DOI: 10.1002/chem.201100428
Keywords
anionic substrates; cage compounds; cryptands; molecular recognition; sensors
Categories
Funding
- Fundacao para a Ciencia e a Tecnologia (FCT) [SFRH/BD/36159/2007]
- Programa Operacional Ciencia e Inovacao (POCTI) [REDE/1517/RMN/2005]
- European Community
- [PTDC/QUI/68582/2006]
- Fundação para a Ciência e a Tecnologia [SFRH/BD/36159/2007, PTDC/QUI/68582/2006] Funding Source: FCT
Ask authors/readers for more resources
A new polyamine macrobicyclic compound was synthesised through a [1+1] tripod-tripod coupling strategy and using a Schiff base condensation reaction, followed by sodium borohydride reduction. The resulting compound is a heteroditopic cage (btpN(7)) in which one of the head units is appropriate for the coordination of copper(II), whereas the other head is available for additional hydrogen-bonding and electrostatic interactions with substrates. The acid-base behaviour of the new compound, the stability constants of its complex with the Cu2+ ion and the association constants of the copper( II) cryptate with oxalate (oxa(2-)), malonate (mal(2-)), succinate (suc(2-)), maleate (male(2-)) and fumarate (fum(2-)) were determined by potentiometry at 298.2 K in aqueous solution and at an ionic strength of 0.10 mol dm(-3) in KNO3. These studies revealed a clear preference of the receptor [CuH(h)btpN(7)H(2)O]((2+h)+) for oxa(2-) over the other dicarboxylate substrates. This arises from co-operativity between metal-anion coordination and electrostatic and hydrogen-bonding interactions, in accordance with the ideal size of this dicarboxylate, which allow it to take full advantage of the potential binding sites of the receptor. A qualitative indicator-displacement study, in agreement with the potentiometric studies, demonstrated that the copper cryptate receptor can be used as a selective visual sensor for oxalate.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available