F. Villain

The first example of a substrate spanning the calix[4]arene bilayer: the solid state complex of p-sulfonatocalix[4]arene with L-lysine

The complex of p-sulfonatocalix[4]arene with L-lysine shows a new type of intercalation behaviour with regard to the achiral hydrophobic bilayer assembly of the calixarenes, and represents the first structural example of a cationic organic substrate spanning such a bilayer.

The Heptakis-(2,6-di-O-methyl)-β-cyclodextrin Inclusion Complex with Acetic Acid

A novel monomer-type structure of heptakis-(2,6-di-O-methyl)-β-cyclodextrin in a typical monoclinic herringbone scheme has been determined by single crystal X-ray diffraction. Crystal data: space group P21, Z = 2, a = 15.165(6), b = 10.613(3), c = 23.188(8) Å, β = 102.02(4)°, V = 3650(3) Å3 and R = 0.094 for 2933 observed MoKα reflections with I > 3σ(I). A unique water molecule located in the intermolecular spaces, reinforces the cohesion between the herringbone chains. The analysis of the electron density distribution suggests that an acetic acid molecule is trapped within the macrocycle cavity, alternately with a water molecule.

Nesting inclusion compounds : the X-ray structure of the 15-crown-5 sodium diphenylethyl diphenylmethyl cyanoacetonate complex

The action of sodium cyanide ongem -diphenyl-chloropropanone under phase transfer conditions in the presence of 15-crown-5 yields the title compound as a minor product. The crystal structure of this complex reveals that, in the solid state, the [15-crown-5-Na+] guest species is found within a loose cage of diphenylethyl diphenyl cyanoacetonate molecules with one open side of the cage blocked by an adjacent 15-crown-5 molecule. Colourless crystals of the compound belong to the monoclinic space groupP21/n witha = 12,255(2) Å,b = 13,005(1) Å,c = 23,433(2) Å, β = 95,92(1) ° andDc = 1.23 g cm−3 forZ = 4.

Molecular recognition by cyclodextrins: the x-ray structure of 6A-boc-L-phenylalanylamino-6A-deoxy-β-cyclodextrin

Abstract The first crystallographic example of a β-cyclodextrin monosubstituted at O6 by a bulky group possessing two terminal apolar side chains, tert-butoxycarbonyl-L-phenylalanylamino (Boc-L-Phe-NH), illustrates an unusual cyclodextrin host/guest organisation. The structure is a novel packing of monomer units. Two symmetry independent Boc-L-Phe-NH-β-CD molecules are stacked parallel to the two-fold screw axis forming two independent alternate ‚endless screw head-to-tail’ channels. Both apolar side chains are at the exterior of the intramolecular cavity and are fully enclosed within the channels: the phenyl ring of the amino residue lies above the parent macrocycle while the tert-butyl group is intermolecularly included within a neighbouring molecule. Water molecules located outside the monomeric cavities over 34 sites, all but one external to the channels, fill the intermolecular spaces and reinforce the cohesion of the structure.

Inclusion of the Main Pheromone Component of Dacus oleae, 1,7-Dioxaspiro[5,5]undecane, in β-Cyclodextrin

The complex beta-cyclodextrin-1,7-dioxaspiro[5,5]undecane nonahydrate, C42H70O35.C9H16O2.9H2O, belongs to the class of beta-cyclodextrin dimeric-type complexes. The racemic guest molecule is present in a disordered position. Both enantiomers are located in two different regions inside the channel formed by the host dimers.

X-ray crystallographic structure of the two-to-one α-cyclodextrin-acetone. 9H2O compound

Abstract An inclusion complex of acetone with α-cyclodextrin (α-CD) has been prepared in aqueous solution containing AG+ ions. The crystal structure of the complex has been determined by single crystal X-ray diffraction. Crystal data: triclinic, space group P1, Z = 1, a = 13.852(1), b = 13.878(1), c = 15.719(1) A, α = 93.01(1), β = 91.98(1), γ = 119.32(1)° and R = 0.069 for 6092 observed MoKα reflections with I > 3σ(I). This crystalline form is of the dimeric-type structure which normally occurs for ionic guest molecules. The dimers are stacked along the c axis to form an ‘endless head-to-head’ channel. Nine water molecules fill the intermolecular space outside the dimeric cavity and contribute to reinforce the cohesion between the channels which are in a pseudo-hexagonal arrangement. The acetone molecule is encapsulated within the cavity of the dimer. Molecular graphics analysis of difference Fourier maps suggests that the acetone molecule is situated in several partially occupied sites forming an infini...

Crystal structure of [mono-O-(diethoxy)thiophosphonato]tetra-tert-butylcalix[4]arene, C18H66O6PS

C48H66O6PS, monoclinic, P\2\ln\ (No. 14), a = 13.563(2) Ä, b = 20.834(3) Ä, c = 17.156(3) Ä, β = 106.86(2)°, V = 4639.5 Ä 3 , Ζ = 4 , R ^ F ) = 0.069, RW(F) = 0 . 1 6 1 , 7 = 2 9 1 K.

Crystal Engineering in Solid-State Metal Salt Complexes of Cyclodextrins

We have developed extensive investigations on the nature of the solid-state cyclodextrin-salt interaction and its effect on the molecular self-organization. The first examples of complexes were provided by β-cyclodextrin with metal chlorides1,2 (calcium and hydrated magnesium). Then, systematic crystallization experiments have been undertaken to determine the conditions for solidstate metal complexation, given the solubilities of α- β- and γ- cyclodextrins as a function of the salt concentration.

Environmental Effects on Molecular Properties of Organic Compounds. Part II. β-Cyclodextrin Inclusion Complexes with Cinnamic Acids.

Abstract β-Cyclodextrin forms inclusion complexes with cinnamic acids. The formation of the inclusion complexes has been established by X-ray powder-diffraction, ultraviolet and induced circular dichroism spectra. Environmental effects on molecular properties of the guest compounds, such as dimerization have been observed in the solid state.