RESUMEN
The title compound, C(13)H(16)O(2)Si, was synthesized as a precursor for ethynylarene derivatives and crystallized from hexane. In the crystal structure, mol-ecules are linked by weak C-Hâ¯O hydrogen bonds to form chains that pack in layers in a herringbone fashion.
RESUMEN
In spite of partial deprotonation upon inclusion of morpholine, Dianin's compound maintains its well-known clathrate structure in the solid state.
RESUMEN
We have studied the hydrogen sorption on three well-known organic hosts that possess vacant lattice voids large enough to accommodate H2 molecules.
RESUMEN
A quasiracemic mixture of Dianin's compound and its thiol derivative enforces additional anisotropy of the guest-accessible space, thus facilitating a net polar arrangement of guest molecules; guest alignment is rationalized in terms of van der Waals volume considerations.
RESUMEN
The title compound, C12H12N2O4S2, crystallizes in white and yellow polymeric forms as a result of interesting anti-anti and syn-anti conformational isomerism of the thiocarbonyl and carbonyl moieties relative to one another. This work is the first reported X-ray crystallographic structure determination of isomers of this class of bipodal ligand. The white form, anti-anti, (I), crystallizes with the benzene ring lying about a twofold rotation axis, resulting in both of the thiocarbonyl and carbonyl moieties being anti relative to each other. The yellow modification crystallizes as syn-anti, (II), with one thiocarbonyl moiety syn and the other anti relative to the respective carbonyl groups. The individual molecules of both (I) and (II) are extensively linked through intermolecular hydrogen bonds. Intermolecular hydrogen bonding in (II) includes a network of bifurcated N-H...O and N-H...S hydrogen bonds, while molecules of (I) include bifurcated C-H...O hydrogen bonds.
RESUMEN
Dianin's compound (4-p-hydroxyphenyl-2,2,4-trimethylchroman) has been resolved by crystallization of the (S)-(-)-camphanic esters (S,S)- and (R,S)-4-(2,2,4-trimethylchroman-4-yl)phenyl 4,7,7-trimethyl-3-oxo-2-oxabicyclo[2.2.1]heptane-1-carboxylate, both C28H32O5, from 2-methoxyethanol, yielding the pure S,S diastereomer. The relative stereochemistry of both diastereomers has been determined by X-ray crystallography, from which the absolute stereochemistry could be deduced from the known configuration of the camphanate moiety. The crystallographic conformations have been analysed, including the 1:1 disorder of the R,S diastereomer.
RESUMEN
The title compound, C(14)H(16)N(2)O(4)S(2), is the first reported X-ray crystallographic structure determination of a bipodal O-alkyl N-benzoylthiocarbamate. This compound crystallizes in a cis-S,O orientation (Z,Z' configuration), with the two S/O moieties anti relative to one another, as indicated by the twofold rotation axis located at the center of the benzene ring.
RESUMEN
The hydroxyl end-groups of Pluronic F108 [a tri-block copolymer surfactant of poly(ethylene glycol) and poly(propylene glycol) [PEG-PPG-PEG]] were converted into primary amine and quaternary ammonium equivalents for use in a new approach to affinity chromatography. The preparation of sulphonic acid end-groups was also attempted.