Roger Lamartine

Synthesis, X-ray crystal structure and complexation properties towards metal ions of new thiacalix[4]arenes

Abstract p-tert-Butyl-tetrakis[(methylcarbonyl)methoxy]tetrathiacalix[4]arene and p-tert-butyl-tetrakis[(benzoyl)methoxy]tetrathiacalix[4]arene were prepared and their conformation was established by X-ray crystallography. p-tert-Butyl-tetrakis[(diethylamide)methoxy]tetrathiacalix[4]arene was also synthesized. The ability of these three macrocycles to bind metal ions was investigated via a solvent extraction study.

The potential industrial applications of calixarenes

Calixarenes can be considered as macrocycles or perfectly defined cyclic oligomers. Their potentiel applications, determined from industrial chemistry publications and existing patents are presented. Non modified calixarenes and calixarenes modified by chemical reactions are successively taken into account. The latter may be considered as molecular platforms to which functional groups are fixed. The described applications concern, recovery of caesium and uranium, lanthanide sequestration, separation of neutral organic molecules, stabilizers for organic polymers, pollution control selective complexation of neutral cations, phase transfer agents, accelerators for instant adhesives, ion scavengers for electronic devices, Langmuir-Blodgett film and membranes, catalytic properties.

An efficient regio-specific synthetic route to multiply substituted acyl-sulphated β-cyclodextrins

Abstract The regio-specific synthesis of a series of novel amphiphilic β-cyclodextrins is described. We are able to check the degree of sulphatation at upper rim and the degree of acylation and over-acylation at lower rim by electrospray mass spectrometry. The 6- O -silyl-2,3- O -acyl-β-cyclodextrin is synthesised in large scale by one pot reaction from β-cyclodextrin. The products are generally mixtures with varying degrees of substitution. These amphiphilic cyclodextrin form micellar aggregates.

2,2′-Bithiazolyl-p-tert-butylcalix[4]arene podands. Synthesis and fluorescence properties

Abstract Five new conic calix[4]arene-based podands incorporating the fluorescent 2,2′-bithiazole subunit have been synthesised and fully characterised. Comparative fluorescence studies shown a decrease of bithiazole Iemfrom the mono- to the tetra-substituted species. Two intramolecular deactivation processes and a “calixarene effect” have been proposed.

Synthesis, characterization and optical power limiting behaviour of phenylazo- and 4-nitrophenylazo-tetrahydroxytetrathiacalix[4]arene

p-Tetrakis(4-nitrophenylazo)tetrahydroxytetrathiacalix[4]arene and p-tetrakis(phenylazo)tetrahydroxytetrathiacalix[4]arene were prepared and fully characterized using 1H and 13C NMR, mass spectroscopy, thermogravimetric analysis and differential scanning calorimetry. The solid-state structure of p-tetrakis(4-nitrophenylazo)tetrahydroxytetrathiacalix[4]arene was investigated by single crystal X-ray diffraction. It crystallized in the triclinic system (space group: P). z-Scan experiments were performed on the p-tetrakis(4-nitrophenylazo)tetrahydroxytetrathiacalix[4]arene showing non linear absorption due to two photon absorption with a TPA cross-section of about 50xa0×xa010−50xa0cm4xa0s per photon. Optical power limiting measurements on the p-tetrakis(phenylazo)tetrahydroxytetrathiacalix[4]arene nat 532xa0nm (48% linear transmission) was found to limit the energy to ∼9xa0µJ.

Wittig reaction on calixarene upper rim. Access to conjugated bipyridyl and pyridyl podands

Abstract Monoformyl-tris-( p -Bu t )calix[4]arene was synthesised and reacted in smooth conditions with phosphonium salts of 6-bromomethyl-6′-methyl-2,2′-bipyridine and 2-chloromethyl-pyridine, affording the corresponding conjugated mono-armed macrocycles.

Quantitative solvent extraction from neutral aqueous nitrate media of silver(I) against lead(II) with a new calix[4]arene-based bipyridine podand

A new calix[4]arene-based podand incorporating two 2,2′-bipyridine and two benzyl units in alternate positions at the lower rim was shown to quantitatively extract silver(I) from neutral aqueous solutions containing a mixture of lead and silver nitrates. The corresponding AgPF6 complex was synthesised and characterised.

Synthesis and extraction properties of multifunctionalized azocalix[4]arenes containing bipyridyl subunits

A series of four azocalixarene derivatives bearing bipyridyl units and additional functional groups such as amide, ester and pyridine at the phenolic oxygen atoms were synthesized. The conformational properties of these ligands were obtained by 1H NMR spectroscopy. Moreover, extraction properties towards different metals of 1, 2, 4, 5 and 6 using liquid–liquid extraction by atomic absorption spectrometry have been studied and exhibit Ag+ selectivity.

Synthesis of calix[4]arene podands bearing two and four histidine or glycine groups at the lower rim. Complexation properties towards cobalt(II) chloride

Abstract Four calix[4]arene podands displaying two or four glycine or histidine arms at the lower rim have been synthesised and fully characterised. Their coordinating behaviour towards cobalt(II) chloride has been investigated.

Synthesis and Characterization of P-tert-Butyl-calix[9, 10, 11 and 12]arenes.

Abstract The p-tert-butylcalix[n]arenes (n = 9, 10, 11, 12) have been co-synthesized in significant amounts from cyclocondensation reaction mixture of linear phenolic oligomers in basic conditions. They have been isolated and fully characterized.