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- PublicationMétadonnées seulement1,1'-Disubstituted ferrocene-containing thermotropic liquid crystals of structure [Fe{(?5-C5H4)COOC6H4XC6H4OCnH2n+1}2] (X = OOC or COO). Influence of the orientation of the central ester function on the mesogenic properties(1993)
; ;Marendaz, Jean LucSantiago, Julio1,1'-Disubstituted ferrocene-contg. thermotropic liq. crystals I and II, which differ in the orientation of the ester function included in the rigid org. part, were synthesized and their liq. crystal properties examd. These latter were strongly dependent on the orientation of the connecting ester group and on the alkyl chain length. [on SciFinder(R)] - PublicationMétadonnées seulement1,3-Disubstituted ferrocene-containing thermotropic liquid crystals: synthesis, mesomorphic properties and the crystal and molecular structure(1993)
; ;Kosztics, Isabelle ;Marendaz, Jean LucTwo families of 1,3-disubstituted ferrocene derivs. were synthesized and their liq.-crystal behavior investigated. Compds. of series I, (?5-C5H5)Fe[(?5-C5H3)-1,3-(COOC6H4OOCC6H4OCnH2n+1)2] (n = 1-14, 16, 18), exhibited remarkable mesomorphic properties. Indeed, nematic and/or smectic C phases, assocd. with large anisotropic domains, were obsd. Derivs. of series II, (?5-C5H5)Fe[?5-C5H3)-1,3-(COOC6H4OCnH2n+1)2] (n = 1-9), were nonmesogenic. The crystal and mol. structure of Ih (n = 8) was detd. by x-ray anal. The compd. is orthorhombic, space group Pnma, with a 7.602(1), b 57.538(3), and c 10.760(1) Å; Z = 4, dc = 1.302; R = 0.102, Rw = 0.132 for 1401 reflections. The crystallog. data confirmed both a highly anisometric structure for Ih and a compact arrangement of the mols. in the crystal. The present results show that a crit. length/depth ratio of approx. 5-7 must be passed for obtaining liq.-crystal properties. [on SciFinder(R)] - PublicationMétadonnées seulement1,4-Bis(hexyloxy)-2,5-diiodobenzene(2010)
; ; ;Sereda, Olha ;Neels, AntoniaThe centrosym. title compd., C18H28I2O2, crystd. in the monoclinic space group P21/c with the alkyl chains having extended all-trans conformations, similar to those in the centrosym. bromo analog that crystd. in the triclinic space group P?1. The difference between the 2 structures lies in the orientation of the 2 alkyl chains with respect to the C(arom.)-O bond. In the title compd., the O-Calkyl-Calkyl-Calkyl torsion angle is 55.8(5)°, while in the bromo analog this angle is -179.1(2)°. In the title compd., the C-atoms of the alkyl chain are almost coplanar [max. deviation of 0.052(5) Å] and this mean plane is inclined to the benzene ring by 50.3(3)°. In the bromo-analog, these 2 mean planes are almost coplanar, making a dihedral angle of 4.1(2)°. Another difference between the crystal structures of the 2 compds. is that in the title compd. there are no halide...halide interactions. Instead, symmetry-related mols. are linked via C-H...? contacts, forming a 2D network. Crystal data: monoclinic, P21/n, a = 9.441(9), b = 7.8455(6), c = 13.457(2) Å, ? = 92.148(12)°, Z = 2, 1216 obsd. reflections with I > 2(I), 101 refined parameters, R[F2 > 2?(F2)] = 0.029, wR(F2) = 0.055. [on SciFinder(R)] - PublicationMétadonnées seulement1,4-Bis[4-(tert-butyldiphenylsilyl)buta-1,3-diynyl]benzene(2010)
; ; The title centrosym. mol., C46H42Si2, is composed of a central benzene ring with buta-1,3-diynyl chains at positions 1 and 4. These chains are terminated by tert-butyldiphenylsilyl groups, hence the mol. is dumbbell in shape. The mols. are connected via C-H...? interactions in the structure, so forming an undulating 2D network in the bc plane. There is also a weak ?-? interaction involving centrosym. related Ph rings with a centroid-centroid distance of 3.8359(11) Å. Crystal data: monoclinic, P21/c, a = 8.535(1), b = 17.2060(14), c = 13.4923(14) Å, ? = 104.064(9)°, Z = 2, 3260 obsd. reflections with I > 2(I), 220 refined parameters, R[F2 > 2?(F2)] = 0.044, wR(F2) = 0.104. [on SciFinder(R)] - PublicationMétadonnées seulement100 GHz passively mode-locked Er: Yb: glass laser at 1.5 ?m with 1.6-ps pulses(2008)
;Oehler, Andreas Ernst Heinz; ;Weingarten, Kurt JKeller, Ursula - PublicationMétadonnées seulement
- PublicationAccès libre10th International Conference on Innovative Internet Community Services (I2CS)(Bonn: GI-Edition, 2010)
; ;Eichler, Gerald ;Lechner, Ulrike ;Meesad, PhayungUnger, Herwig - PublicationMétadonnées seulement
- PublicationMétadonnées seulement16.2-W average power from a diode-pumped femtosecond Yb: YAG thin disk laser(2000)
;Aus der Au, Jürg ;Spühler, GJ; ;Paschotta, Rüdiger ;Hövel, R ;Moser, M ;Erhard, S ;Karszewski, M ;Giesen, AKeller, Ursula - PublicationMétadonnées seulement
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- PublicationMétadonnées seulement2,2'-(Propane-2,2-di-yl)bis-(1H-pyrrole)The title compound, C(11)H(14)N(2), crystallized with two independent mol-ecules (A and B) in the asymmetric unit. The two mol-ecules differ only slightly, with the pyrrole rings being inclined to one another at a dihedral angle of 87.67 (8)° in mol-ecule A and 88.09 (7)° in mol-ecule B. In the crystal, there are no classical hydrogen bonds, but the two pyrrole NH groups of one mol-ecule are involved in N-H(midline ellipsis)? inter-actions with the pyrrole rings of the other mol-ecule. In this manner, a compact box-like arrangement of the two independent mol-ecules is formed.
- PublicationMétadonnées seulement2,2'-(Propane-2,2-diyl)bis(1H-pyrrole)2,2'-(Propane-2,2-diyl)bis(1H-pyrrole), C11H14N2, crystd. with 2 independent mols. (A and B) in the asym. unit. The 2 mols. differ only slightly, with the pyrrole rings being inclined to 1 another at a dihedral angle of 87.67(8)° in mol. A and 88.09(7)° in mol. B. In the crystal, there are no classical H bonds, but the 2 pyrrole NH groups of 1 mol. are involved in N-H···? interactions with the pyrrole rings of the other mol. In this manner, a compact box-like arrangement of the 2 independent mols. is formed. Crystallog. data are given. [on SciFinder(R)]
- PublicationMétadonnées seulement2,3,4,7-Tetrahydro-1H-inden-2-ol: synthesis, molecular structure and coordination chemistry(2004)
;Vieille-Petit, Ludovic; 2,3,4,7-Tetrahydro-1H-inden-2-ol (1) has been synthesized by Birch redn. of indan-2-ol. A single-crystal x-ray structure anal. of 1 shows the compd. to exist as hydrogen-bonded polymers along the c-axis due to the presence of a series of hydrogen-bonds between hydroxo functions. The ferrocene ester derivs., ferrocene carboxylic acid 2,3,4,7-tetrahydro-1H-inden-2-yl ester (2) and ferrocene carboxylic acid indan-2-yl ester (3) have been prepd. by peptidic coupling of ferrocene carboxylic acid with 1 and with indan-2-ol, resp. The single-crystal x-ray structure anal. of 2 and 3 reveal in both cases the cyclopentadienyl rings to adopt an eclipsed conformation with the indenyl substituent being rotated out of the Cp ester plane by almost 90°, allowing no efficient interaction between the ?-system of the Cp ring and the indene moiety. The dienyl deriv. 2 reacts with RuCl3 · nH2O in refluxing ethanol to afford [Ru(arene)Cl2]2 (4) (arene = ferrocene carboxylic acid indan-2-yl ester) as a mixt. of isomers. [on SciFinder(R)] - PublicationMétadonnées seulement[2,6-Bis(3,4-dihydro-2H-pyrrol-5-yl)pyridine-?3N]trichlororhodium(III) monohydrate(2003)
; Crystals of the title compd. are monoclinic, space group C2/c, with a 18.682(4), b 14.821(3), c 14.819(3) Å, ? 126.57(3)°; Z = 8, dc = 1.776; R = 0.036, Rw(F2) = 0.079 for 3136 reflections. The mononuclear octahedral Rh(III) complex shows a H bond between the equatorial Cl atom and the solvent H2O mol. [on SciFinder(R)] - PublicationMétadonnées seulement[2,6-Bis(3,4-dihydro-2H-pyrrol-5-yl)pyridine]trichlororhodium(III) dibenzene solvate(2002)
; ; ;Bernauer, KlausCrystals of the title compd. are monoclinic, space group C2/c, with a 11.434(2), b 10.630(2), c 20.948(4) Å, ? 100.12(3)°; Z = 4, dc = 1.534; R = 0.026, Rw(F2) = 0.059 for 2341 reflections. The structure of the mononuclear octahedral Rh(III) complex possesses a 2-fold axis passing through Rh, the equatorial Cl atom and the N atom pyridine ring. [on SciFinder(R)]