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Titolo:
Synthesis and binding properties of iiii (4i) stereoisomers of phosphonatocavitands - Cooperative effects in cation complexation in organic solvents
Autore:
Delangle, P; Mulatier, JC; Tinant, B; Declercq, JP; Dutasta, JP;
Indirizzi:
Ecole Normale Super Lyon, UMR CNRS 5532, F-69364 Lyon 07, France Ecole Normale Super Lyon Lyon France 07 RS 5532, F-69364 Lyon 07, France Univ Catholique Louvain, Chim Phys & Cristallog Lab, B-1348 Louvain, Belgium Univ Catholique Louvain Louvain Belgium B-1348 , B-1348 Louvain, Belgium
Titolo Testata:
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
fascicolo: 19, , anno: 2001,
pagine: 3695 - 3704
SICI:
1434-193X(200110):19<3695:SABPOI>2.0.ZU;2-B
Fonte:
ISI
Lingua:
ENG
Soggetto:
HOST-GUEST COMPLEXATION; NUCLEAR MAGNETIC-RESONANCE; ANION INCLUSION; ALKALI-METAL; MACROCYCLIC PHOSPHONAMIDES; MOLECULAR-STRUCTURE; CESIUM; CALIXARENE; CRYPTANDS; CHEMISTRY;
Keywords:
cations; cavitands; NMR spectroscopy; supramolecular chemistry; X-ray diffraction;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Physical, Chemical & Earth Sciences
Citazioni:
57
Recensione:
Indirizzi per estratti:
Indirizzo: Dutasta, JP Ecole Normale Super Lyon, UMR CNRS 5532, F-69364 Lyon 07, France Ecole Normale Super Lyon Lyon France 07 9364 Lyon 07, France
Citazione:
P. Delangle et al., "Synthesis and binding properties of iiii (4i) stereoisomers of phosphonatocavitands - Cooperative effects in cation complexation in organic solvents", EUR J ORG C, (19), 2001, pp. 3695-3704

Abstract

Syntheses and host-guest properties of tetrabridged phosphorylated cavitands in their iiii (4i) configurations are described, The tetraphosphonato cavitands 2 and 3, with the four P=O bonds oriented inwards (4i stereoisomer)were prepared in 25% and 53% yields respectively, from the corresponding resort[4]arenes, dichloro(phenyl)phosphane oxide and base. The formation of the 4i stereoisomers is solvent-dependent and is attributable to the capability of an ammonium guest to form an inclusion complex. Only the iiio (3io)stereoisomer of 3 was isolated otherwise, in low yield. These phosphonato cavitands, in their 4i configurations, are particularly efficient extractants for metal ions. The free energies of complexation of 3 with alkali metaland ammonium cations in chloroform solution are in the range from -43.3 (Li+) to -52.4 kJ mol(-1) (CH3NH3+). High binding constants, H-1, P-31 and Cs-133 NMR studies in solution and single-crystal X-ray analysis clearly demonstrated that the aromatic cavity of the host and the four hard donor P=O groups act cooperatively to ensure the encapsulation of the cationic guests. In the solid, the 2 . Cs+ complex showed the Cs' ion inside the aromatic cavity, interacting strongly with the four phosphoryl groups. The 2 . CH3NH3 complex showed the methyl group of the guest oriented inside the cavity, with the stability of the complex supported by a complex H bond pattern involving H2O molecules and the anion.

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Documento generato il 23/09/20 alle ore 13:03:33