Isostructural lanthanide-based coordination polymers with general chemical formula [Ln­(phen)­(glu)­(NO3)]∞ with Ln = La–Tm (except Ce and Pm) have been synthesized by hydrothermal methods (H2glu stands for glutaric acid and phen stands for 1,10-phenantroline). They crystallize in the monoclinic system with the P21/c (no. 14) space group. The crystal structure has been solved on the basis of the La derivative. It can be described as the superimposition of molecular chains of dimeric La­(phen)­(NO3)-La­(phen)­(NO3) units bridged by glutarate ligands. Luminescent properties have been explored and show that the Eu derivative exhibits the highest luminance observed for Eu-based coordination polymers (85 to 105 cd·m–2). Effects of the dilution of the Eu3 + and Tb3 + luminescent ions by Gd3 + optically inactive ions are unexpected and to the best of our knowledge unprecedented. This could be related to the different intermetallic energy-transfer mechanisms in competition and to the nonisotropic distribution of the lanthanide ions in these molecular alloys. The investigation of molecular alloys with general chemical formula [Eu1–x Tb x (phen)­(glu)­(NO3)]∞ with 0 ≤ x ≤ 1 highlights a very sizable and constant Eu3 + luminescence whatever the x value, which further confirms the existence of very strong intermetallic energy transfers in this family of compounds. It is also noticeable that some coordination polymers based on weakly emissive lanthanide ions exhibit very well defined emission spectra.

1,3-Bis[bis(4-tert-butylphenyl)chloromethyl]benzene and 1,3-bis[bis(4-anisyl)chloromethyl]benzene were employed as regioselective capping reagents for the preparation of C-6A,C-6B-bridged, permethylated alpha- and beta-CD derivatives; isolated yields up to 55% of proximally capped, methylated CDs were obtained, thus opening the way to the straightforward preparation of a wide range of A,B-functionalised CDs. As revealed by a single crystal X-ray diffraction study, the benzene-1,3-bis[bis(4-tert-butylphenyl)methyl] spacer is perfectly suited for A,B-capping of beta-cyclodextrin.

An efficient thioglycosylation of C(sp )-H bonds with thiosugars has been established for the first time. Using only Cu(OAc) ⋅H O as a catalyst and Ag CO as an additive in DMSO, the protocol proved to have broad scope, and a variety of complex thioglycosides have been prepared in good yields with exclusive β-selectivity.

Six lanthanides complexes with chemical formula [Ln(phen)2(NO3)3] (Ln = Sm(1), Tb (2), Nd (3), Eu (4), Ho (5) and Y (6), phen = 1,10-phenanthroline) were synthesized. 1 and 2 were obtained as single crystals by slow diffusion. Structural characterization was based on single crystal X-ray diffraction and IR and 89 Y-NMR spectroscopies. NMR spectroscopic measurements were performed on [Y(phen)2(NO3)3] (6) and [Y0.75Lu0.25(phen)2(NO3)3] (7). Compounds obtained as microcrystalline powders were characterized by powder X-ray diffraction. The complexes crystallize in the monoclinic system, space group P21/n. Each Ln(III) ion is surrounded by four N atoms from two bidentate phenanthroline ligands and six O atoms from three chelating nitrate groups. The phenanthroline ligand provides efficient sensitization of the complexes that exhibit sizeable luminescence under UV irradiation. Thermal properties have been studied. They confirm the absence of water molecules in the crystal structure. The complexes are thermally stable up to 290 °C. Microcrystalline powders of hetero-lanthanide complexes, with global chemical formula [Tb1-xEux(phen)2(NO3)3] (series 8) and [Tb1-xGdx(phen)2(NO3)3] (series 9) were synthesized. Their photo-physical properties have been investigated. They demonstrate that luminescent molecular alloys can be obtained from lanthanides complexes and not only from hetero-nuclear coordination polymers as previously reported.

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