In the crystal structure of the title compound, NH(4) (+)·PF(6) (-)·C(12)H(24)O(6), the cation is situated in the 18-crown-6 ring, forming a supra-molecular rotator-stator-like structure held by N-H⋯O hydrogen bonds. The six O atoms of the crown ether lie approximately in a plane [mean deviation 0.2129 (3) Å]; the N atom is displaced by 0.864 (3)Å from the centroid of the 18-crown-6 ring. The s...

The reaction of dimethyl-amine hydro-chloride, 18-crown-6 and ferric chloride in ethanol yields the title compound, (C(2)H(8)N)[FeCl(4)]·C(12)H(24)O(6), which exhibits an unusual supramolecular structure. The protonated dimethyl-amine contains one NH(2) (+) group, resulting in a 1:1 supra-molecular rotator-stator structure (CH(3)-NH(2) (+)-CH(3))(18-crown-6), through N-H⋯O hydrogen-bonding inte...

The synthesis, complexation properties and catalytic activities under phase-transfer (PT) conditions of differently substituted cyclohexapeptoids are reported. Association constants, for small cationic alkali, and catalytic performances, in a model nucleophilic substitution, are comparable to those of representative crown ethers. Noteworthy, the N-[2-(2-methoxyethoxy)ethyl] side chain derivativ...

A novel [2]pseudorotaxane was successfully constructed by the complexation of dibenzo[24]-crown-8 (DB24C8) derivative bearing terpyridine moiety (1) with lanthanide ion (Tb(3+)) and fullerene-containing ammonium salt (2), exhibiting the controlled photophysical behaviors as a reversible luminescent lanthanide switch in the presence of K(+) or 18-crown-6 (18C6).

The reaction of benzyl-ammonium tetra-fluoro-borate and 18-crown-6 in a methano-lic solution yields the title compound, C(7)H(10)N(+)·BF(4) (-)·C(12)H(24)O(6)O6, which displays a supra-molecular structure. The -NH(3) (+) substituent of the benzyl-ammonium cation forms a 1:1 supra-molecular rotator-stator structure by N-H⋯O hydrogen-bonding inter-actions.

In the title compound, 2CH(6)N(3) (+)·2Br(-)·C(12)H(24)O(6), the 18-crown-6 mol-ecule lies about an inversion center, whereas the guanidinium cation and bromide anion are in general positions. The guanidinium cations link with the bromide anions and the crown ether mol-ecules via N-H⋯O and N-H⋯Br hydrogen bonds, thus forming a three-dimensional network.

The reaction of 4-fluoro-aniline hydro-chloride, 18-crown-6 and ferric chloride in methano-lic solution yields the title compound, (C(6)H(7)FN)[FeCl(4)]·C(12)H(24)O(6), which has an unusual supramolecular structure. N-H⋯O hydrogen-bonding inter-actions between the NH(3) (+) substituents of the 4-fluoro-anilinium cations and the O atoms of the crown ether mol-ecules result in a rotator-stator-li...

The X-ray structure of the 1:2 host-guest complex between 1,4,7,10,13,16-hexaoxacyclooctadecane (18-crown-6) and 2,4-dinitrophenylhydrazine is reported. Crystallography data are: space group P2i/c, a = 8.557(2), b = 16.745(6), c = 12.387(4) Ä, ß = 117.08(13)°, Z = 2, D m = 1.37 g • cm"3, D c = 1.387 g • cm-3 , m.p. 414 K (decomp.). The present B is 0.11 for 1733 diffractometer data. In the comp...

Crown ethers 12-crown-4 (12C4), benzo-15-crown-5 (B15C5), 18-crown-6 (18C6), nitrobenzo-18-crown-6 (NB18C6) dibenzo-18-crown-6 (DB18C6) and dicyclohexyl-18-crown-6 (DC18C6), dissolved in dichloromethane, are able to form oxonium-ion complexes in contact with aqueous sulfuric and hydrochloric acid solutions. This ability allows the transfer of Cr(VI) oxanions from the acid media, through an ...