1,8-Bis[3-(triethoxy­silyl)prop­yl]-1,8-diazo­niatricyclo­[9.3.1.14,8]hexa­decane diiodide

The organic mol­ecule of title compound, C30H66N4O6Si2 2+·2I−, is located around a centre of symmetry. The structure exhibits disorder of the trieth­oxy groups with the ratios 0.78 (1)/0.22 (1), 0.67 (1)/0.33 (1) and 0.58 (1)/0.42 (1)

Synthèse de polyamines cycliques, compréhension des mécanismes pour la mise au point de méthodes propres, sélectives, économes en atomes et en énergie

Les nombreux domaines d applications des polyamines cycliques nécessitent de mettre au point des synthèses de précurseurs toujours plus performantes. Nous avons développé de nouvelles méthodes permettant d accéder aisément et rapidement à toute une gamme de ligands macrocycliques. L outil bisaminal nous a permis de proposer une nouvelle méthode de synthèse One Pot du cyclame et du [13]aneN4 extrêmement performante. Cette nouvelle synthèse permet ainsi de préparer aisément à l échelle du kilogramme ces ligands macrocycliques dont les domaines d applications ne cessent de croître. Une nouvelle voie d accès à des dérivés monooxomacrocycliques a été exposée grâce à l utilisation d intermédiaires de type bisaminal obtenus par condensation d un dérivé a-dicarbonylé sur un nouveau précurseur triamine-amide. La facilité d accès à ces macrocycles a permis de préparer de nouveaux ligands N-fonctionnalisés dont les propriétés de coordination restent à étudier. L action du chloroacétaldéhyde, en présence de benzotriazole, sur des intermédiaires bisaminal, permet en présence de divers agents nucléophiles d accéder directement à de nouveaux dérivés du [13]aneN4 ou du cyclène C-fonctionnalisés. Cette méthode permet l obtention d agents bifonctionnels chélatants. Des macrocycles originaux ont ainsi été synthétisés et leur réactivité a été étudiée. Enfin une nouvelle voie d accès à des macrocycles triazotés a été mise au point, sans étape de cyclisation. Cette méthode permet à la fois d accéder au 1,4,7-triazacyclononane et à des dérivés sélectivement C- et/ou N-fonctionnalisé. Les propriétés de ces nouveaux ligands tridentates restent à étudier. Le développement de cette nouvelle synthèse va permettre de préparer en aval de nouveaux ligands possédant une sélectivité élevée vis-à-vis d un substrat donné.DIJON-BU Sciences Economie (212312102) / SudocSudocFranceF

Crystal structure of di-μ-hydroxido-bis{aqua[ethyl (1,10-phenanthrolin-3-yl)phosphonato-κ2N,N′]copper(II)} heptahydrate

In the title compound, [Cu2(OH)2{C12H7N2(PO3C2H5)}2(H2O)2]·7H2O, two Cu2+ cations are bridged by two hydroxide groups, forming a centrosymmetric binuclear complex. Each Cu2+cation is further coordinated by the N atoms of a bidentate ethyl (1,10-phenanthrolin-3-yl)phosphonate anion and a water molecule in a square-pyramidal geometry. In the crystal, a network of O—H...O hydrogen bonds involving the P(O)(O−)(OEt) groups, bridging hydroxyl groups, coordinated and uncoordinated water molecules generates a three-dimensional supramolecular structure. The ethyl group exhibits disorder and was modelled over three sites with occupancies of 0.455, 0.384 and 0.161

Designing P-Chirogenic 1,2-Diphosphinobenzenes at Both P-Centers Using P(III)-Phosphinites

International audienceA new enantiodivergent synthesis of P-chirogenic 1,2-diphosphinobenzenes (DP*B) bearing the chirality on one or both phosphorus centers is reported using aryne chemistry. The principle is based on successive reactions of 1,2-dibromobenzene with sec-phosphide boranes, then DABCO to remove the borane, and finally with chlorophosphines or P(III)-chirogenic phosphinites. The efficiency of this synthesis was demonstrated by the stereoselective preparation of (S,S)-1,2-bis(o-anisylphenylphosphino)benzene. A comparison of DIPAMP and homochiral DP*B ligands in asymmetric Rh- or Pd-catalyzed reactions was reported

Pyrene/coumarine-subphthalocyanine conjugates as light harvesting systems with intramolecular energy transfer

International audienceA series of subphthalocyanine-antenna dyads have been successfully designed, synthetized and characterized by 1H-NMR, 13C-NMR, high-resolution mass spectroscopy, and X-ray diffraction studies with one dyad. Pyrene and coumarine have been appended at the axial position of the subphthalocyanine scaffold using different types of linkers. Photophysical properties of the new compounds have been measured in toluene, tetrahydrofuran, chloroform, dimethyl sulfoxide and methanol. Energy transfer efficiencies between antenna and the subphthalocyanine platform have been investigated and almost quantitative energy transfer occurs in the antenna-platform 5

Crystal structure of (R)-6-fluoro-2-[(S)-oxiran-2-yl]chroman

The title compound, C11H11FO2, is a building block in the synthesis of the active pharmaceutical ingredient dl-nebivolol. The synthesis starting from the enantiomerically pure (R)-6-fluoro-4-oxo-3,4-dihydro-2H-chromene-2-carboxylic acid resulted in a mixture of two stereoisomers, namely (R)-6-fluoro-2-[(S)-oxiran-2-yl]chroman and (R)-6-fluoro-2-[(R)-oxiran-2-yl]chroman. The mixture was separated by column chromatography but only one stereoisomer crystallized. The X-ray structure analysis revealed that the solid consisted of the R,S isomer. A similar procedure was repeated for (S)-6-fluoro-4-oxo-3,4-dihydro-2H-chromene-2-carboxylic acid and, in this case, the S,R isomer was produced as a crystalline solid. Thus, all four stereoisomers of the title epoxide were obtained and their absolute configuration was assigned. The crystal studied was refined as an inversion twin

(R)-(−)-Quinuclidin-3-ol

The structure of the title compound [alternatively called (R)-(−)-1-azabicyclo[2.2.2]octan-3-ol], C7H13NO, at 100 K has hexagonal (P61) symmetry. The structure shows a twist along the C—N pseudo-threefold axis. In the crystal, molecules are linked via O—H...N hydrogen bonds, forming infinite chains along the c-axis direction. The crystal studied was twinned by merohedry (twin law: 010, 100, 00-1; population: 0.925:0.075

(S,S,S,S)-Nebivolol hydrochloride hemihydrate

The asymmetric unit of the title hydrated salt, C22H26F2NO4+·Cl−·0.5H2O, consists of an (S,S,S,S)-nebivolol {nebivol = bis[2-(6-fluoro-3,4-dihydro-2H-1-benzopyran-2-yl)-2-hydroxyethyl]ammonium} cation, a chloride anion and a half-occupancy water molecule. The dihedral angle between the mean planes of the benzene rings is 50.34 (12)°. The pyran rings adopt half-chair conformations. The crystal packing features O—H...O hydrogen bonds and weak N—H...Cl, O—H...Cl, and O—H...Cl interactions, producing layers along (010)

A triclinic polymorph of (−)-(S)-N-benzyl-2-[(R)-6-fluorochroman-2-yl]-2-hydroxyethanaminium bromide

The title salt, C18H21FNO2+·Br−, determined at 115 K, crystallizes in the triclinic space group P1. The previously reported polymorph occurs in the monoclinic space group P21 and has two independent molecules in the asymmetric unit [Peeters et al. (1993). Acta Cryst. C49, 2157–2160]. In the title molecule, the pyran rings adopt half-chair conformations. The absolute configuration is S for the hydroxy-bearing C atom and R for the asymmetric C atom in the dihydropyran unit. In the crystal, the components are linked by N—H...Br and O—H...Br hydrogen bonds, forming chains along the c-axis direction. The crystal studied was refined as an inversion twin