RESUMEN
The title host compound, C62H84N4O4, designed to self-assemble to form a new type of extended core Piedfort unit reminiscent of an eight-legged spider host, forms a number of crystalline inclusion compounds favouring oxygen-containing guest mol-ecules. We have established the presence of this unit in the unsolvated mol-ecular crystal at 100â K, which is monoclinic, space group P21/n, with Z = 8. The new Piedfort unit is chiral and its core structure closely approximates to D 2 symmetry, with both enanti-omers present in the crystal. Rather than being superposed with a staggered arrangement of nitro-gen atoms, the rings are rotated by an angle of approximately 45° with respect to each other, and the shortest contact between them is 3.181â (2)â Å. The compound's significant inclusion properties may be taken to suggest the participation of an extended Piedfort unit in the microcrystalline adducts formed. The presence of such a dimeric host unit in the clathrates has, however, not yet been established because of the current lack of suitable single crystals for X-ray analysis.
RESUMEN
The title sulfoxide, C18H20O2S, was prepared by controlled oxidation of thia-Dianin's compound using hydrogen peroxide in glacial acetic acid. On recrystallization from glacial acetic acid, it was found to form unsolvated, spontaneously resolved crystals, the initial crystal structure analysis revealing the presence of both sulfoxide epimers in the crystal. On multiple recrystallization a single epimer was observed, with crystallization occurring in the unchanged ortho-rhom-bic space group P212121, with Z' = 1. The mol-ecule possesses a distal conformation, referring to the juxtaposition of the p-hydoxyphenyl substituent with respect to its syn-related methyl group, with the sulfoxide oxygen atom anti to the aromatic substituent. The mol-ecular packing features O-Hâ¯O hydrogen bond chains running parallel to the b axis of the unit cell.
RESUMEN
The R-(+)-enantiomeric form of Dianin's compound and the S-(+)-enantiomeric form of its direct thiachroman analogue both obtained chromatographically employing a cellulose tris(3,5-dimethylphenylcarbamate) column, are shown to undergo supramolecular assembly to form a polar clathrate lattice which is stable even in the absence of a consolidating guest component.
RESUMEN
The title tetrasulfone 1, in common with higher members of the multi-armed aromatic hosts, forms host-guest complexes with polar guest molecules. In the sulfolane and cycloheptanone complexes the host molecule possesses an abab conformation with exact C(2,) and approximate D(2) symmetry with deviations owing to crystal packing forces. The conformation of the well-ordered cycloheptanone molecule, which normally undergoes facile pseudorotation, is unambiguously defined in the voids of the crystalline inclusion compound.
RESUMEN
Octakis(m-tolyloxymethyl)naphthalene, the first Type I spider host produced, crystallises from tetraglyme forming a novel channel structure with the host molecule attaining exact D(2) symmetry. The (flexible) channel structure is retained for guest CS(2), the host now only having exact C(2) symmetry. The octa-sulfone octakis(m-tolylsulfonylmethyl)naphthalene is also of Type I in its triclinic DMSO clathrate. DNMR establishes a substantial difference in molecular flexibilities in solution.