Nitrobenzofurazan derivatives are well known for their fluorescence, whilst crown ethers complexing capacity toward cationic species. In this study, we present the synthesis and structural characterization of a new derivative containing both nitrobenzofurazan moieties ether core. The compound was obtained from dibenzo-18-crown-6 ether, which first nitrated, reduced to corresponding amine, subse...

Single-crystal X-ray analysis of the 5'-bromo-l',3'-xyly~-l8-crown-5* tert-butylammonium hexafluorophosphate complex shows that the complex is of the "nesting" type in which the cation and the aryl group are on the same face of the macroring and that the macroring has a (ag'a)(ag-a)lag'a)(ag-a)(ag'a)lag-a) eonformation. Among crown ethers with aryl-sub-units, 1' ,3'-xylyl crown ethers (1) have ...

Liquid-liquid extractive-spectrophotometric studies of sodium ion complexes of 18crown-6(18C6), dibenzo-18-crown-6(DB18C6), 15-crown-5(15C5), and 12-crown-4(12C4) and anionic dyes [4-(2-pyridylazo)-resorcinol monosodium salt monohydrate (PAR), Eriochrom Black T (EBT), and methyl orange (MOR)] and sodium picrate (PICRAT) as the counter ion are described. The overall extraction equilibrium consta...

[reaction: see text]. Synthesis of novel dithiane-spiro-crown ethers starting from 5,5-di(hydroxymethyl)-1,3-dithiane is developed. These compounds can be used as building blocks to assemble photolabile bis-crown ethers via addition to dicarbonyl-containing tethers, e.g., isophthalic aldehyde. It is found that unlike their mono-crown precursors such bidentate bis-crowns are capable of efficient...

A variety of switch—functionalized crown ethers have been synthesized. They change their chemical and physical properties in response to the stimuli from the outside world such as light, redox, heat, etc. These novel crown ethers act as ion carriers in membrane transport systems. The rate of ion transport can be thus controlled by an on—off—type switch.

Colloidal inorganic nanocrystals (NCs), functionalized with inorganic capping ligands, such as metal chalcogenide complexes (MCCs), have recently emerged as versatile optoelectronic materials. As-prepared, highly charged MCC-capped NCs are dispersible only in highly polar solvents, and lack the ability to form long-range ordered NC superlattices. Here we report a simple and general methodology,...

(R,R)- and (S,S)-enantiomers of anthracene-containing pyridino-18-crown-6 ether having tert-butyl groups at the stereogenic centers were prepared with aim achieving higher enantioselectivity than for reported (S,S)-analogue isobutyl groups. The enantiomeric recognition abilities new sensor molecules toward chiral protonated primary amines amino acid esters studied in acetonitrile by UV–vis fluo...

Macrocyclic compounds (crown ethers), specifically 18-crown-6 (18-C-6), benzo-15-crown-5 (B-15-C-5), di-benzo-18-crown-6 (DB-18-C-6) and di-cyclohexano-18-crown-6 (DC-18C-6), are used as extractants as well as synergists with amine-group extractants. Platinum and rhodium belong to platinum-group metals (PGMs) and have very similar ionic radii and similar properties. The separation of PGMs is mo...

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 asymmetric unit of the title compound, H(3)O(+)·ClO(4) (-)·C(20)H(24)O(6), contains two mol-ecules/ions of each species. Both dibenzo-18-crown-6 mol-ecules have a complexed hydro-nium ion inside their cavity with O-H⋯O and O-H⋯(O,O) links between the two species. The associated perchlorate anions also accept O-H⋯O hydrogen bonds from the hydro-nium ion. Both crown ether mol-ecules are prese...