14174-09-5

Usage

InChI:InChI=1/C24H32O8/c1-2-6-22-21(5-1)29-17-13-25-9-10-27-15-19-31-23-7-3-4-8-24(23)32-20-16-28-12-11-26-14-18-30-22/h1-8H,9-20H2

Upstream product

• 56604-27-4 C₂₄H₃₂O₈*Na⁽¹⁺⁾ 
• 120-80-9 benzene-1,2-diol 
• 112-26-5 1,2-bis(2-chloroethoxy)ethane 
• 540495-04-3 C₇H₈O₃S*C₁₄H₁₅N*C₂₄H₃₂O₈ 
• 19249-03-7 triethylene glycol di-(p-toluenesulfonate) 
• 77544-68-4 8-tosyloxy-3,6-dioxaoctanol 
• 88037-68-7 1,2-bis{2-[2-(2-hydroxyethoxy)ethoxy]ethoxy}benzene 
• 240797-46-0 1,2-bis{2-[2-(2-tosylethoxy)ethoxy]ethoxy}benzene 

Downstream Products

• 17455-23-1 cis-syn-cis dicyclohexano-24-crown-8 
• 102101-76-8 2,5,8,11,18,21,24,27-Octaoxa-tricyclo[26.4.0.0^12,17]dotriaconta-1⁽³²⁾,12⁽¹⁷⁾,13,15,28,30-hexaene; compound with picric acid 
• 121561-12-4 m,m'-ditosyldibenzo-24-crown-8 
• 121561-14-6 m,m'-ditosyldibenzo-24-crown-8 

Relevant academic research and scientific papers

Conductance study of binding of some Rb+ and Cs+ ions by macrocyclic polyethers in acetonitrile solution

A conductance study of the interaction between Rb+ and Cs+ ions and 18-crown-6 (18C6), dicyclohexyl-18-crown-6 (DC18C6), dibenzo-18-crown-6 (DB18C6), dibenzo-24-crown-8 (DB24C8), and dibenzo-30-crown-10 (DB30C10) in acetonitrile solution has been carried out at various temperatures. The formation constants of the resulting 1:1 complexes were determined from the molar conductance-mole ratio data and found to vary in the order DC18C6 > 18C6 > DB30C10 > DB18C6 ～ DB24C8 for Rb+ ion and DC18C6 > 18C6 > DB30C10 ～ DB24C8 > DB18C6 for Cs+ ion. The enthalpy and entropy of complexation were determined from the temperature dependence of the formation constants. The complexes with the 18-crowns are both enthalpy and entropy stabilized while, in the case of large crown ethers, the corresponding complexes are enthalpy stabilized but entropy destabilized.

A Conductance Study of the Association of Alkali Cations with 1,13-Dibenzo-24-Crown-8 in Acetonitrile

A conductance study concerning the association of Na+, K+, Rb+, and Cs+ with 1,13-dibenzo-24-crown-8 in acetonitrile has been carried out at 35, 30, 25, 20, and 15 deg C.The observed molar conductivities Λ were found to decrease significantly for mole ratios less than unity.A model involving 1:1 stoichiometry has been used to analyze the conductivity data.The stability constant, K, and the molar conductivity Λc for each 1:1 complex were determined from the conductivity data by using a nonlinear least squares curve fitting procedure.The binding sequence, based on the value of log K at 25 deg C, is found to be Rb+>Cs+>K+>Na+.Values of ΔH0 and ΔS0 are reported and their significance is discussed.

Which One is Bulkier: The 3,5-Dimethylphenyl or the 2,6-Dimethylphenyl Group? Development of Size-Complementary Molecular and Macromolecular [2]Rotaxanes

We developed novel size-complementary molecular and macromolecular rotaxanes using a 2,6-dimethylphenyl terminal group as the axle-end-cap group in dibenzo-24-crown-8-ether (DB24C8)-based rotaxanes, where the 2,6-dimethylphenyl group was found to be less bulky than the 3,5-dimethylphenyl group. A series of molecular and macromolecular [2]rotaxanes that bear a 2,6-dimethylphenyl group as the axle-end-cap were synthesized using unsubstituted and fluorine-substituted DB24C8. Base-induced decomposition into their constituent components confirmed the occurrence of deslipping, which supports the size-complementarity of these rotaxanes. The deslipping rate was independent of the axle length but dependent on the DB24C8 substituents. A kinetic study indicated the rate-determining step was that in which the wheel is getting over the end-cap group, and deslipping proceeded via a hopping-over mechanism. Finally, the present deslipping behavior was applied to a stimulus-degradable polymer as an example for the versatile utility of this concept in the context of stimulus-responsive materials.

Multi-gram syntheses of four crown ethers using K+ as templating agent

Dibenzo-30-crown-10 (DB30C10, 1c), dibenzo-24-crown-8 (DB24C8, 1a), 4-carbomethoxydibenzo-24crown-8 (1b) and a new crown ether, 4-carbomethoxydibenzo-30-crown-10 (1d), were synthesized by a simple, high yielding, three-step method. Potassium ions from the highly soluble KPF6 were employed to template the cyclization step, which resulted in very high isolated yields (80-90%).

Interactions between protonated Amine, aza crown ether, and cryptand with dibenzocrown ether studied by a new spectrophotometric technique

The stability constants for the complexation of a diprotonated diamine, a diaza crown ether, and a cryptand with dibenzo-18-crown-6 and dibenzo-24-crown-8, have been studied in aqueous solution using a new spectrophotometric technique. Because of the complex formation, the solubility of the dibenzocrown ethers increases. Complex formation is possible between diamines and dibenzocrown ethers with both 1:1 and 2:1 stoichiometry. However, experimental data are insufficient to decide on the actual stoichiometry of the complexes formed. By computing the stability constants and comparing them with the corresponding results for monoamines, it is possible to decide on the actual stoichiometry of the complexes. Under the experimental conditions only 1:1 complexes with diamines are formed.

Is the tert-butyl group bulky enough to end-cap a pseudorotaxane with a 24-crown-8-ether wheel?

(Chemical equation presented) Although rotaxane chemists have long believed that the tert-butyl group is bulkier than the cavity of dibenzo-24-crown-8- ether (DB24C8), it is essentially smaller than the cavity of DB24C8. The tert-butyl (or 4-tert-butylphenyl) group can actually function as an end-cap of DB24C8-based rotaxanes when the intercomponent interaction is effectively operative. When such attractive interaction is removed, deslippage occurs.

Disaggregation reaction of [2]Pseudorotaxanes composed of dibenzo[24]crown-8 and dialkylammonium having isopropyl end groups

[2]Pseudorotaxanes composed of dibenzo[24]crown-8 (DB24C8) and dialkylammonium having isopropyl end groups are converted into the component molecules in C6D6 solution containing PF6 - anion.

Discrepancy Regarding the Dethreading of a Dibenzo-24-crown-8 Macrocycle through a Perfluorobutyl End in [2]Pseudorotaxanes

Here are reported the synthesis and characterization of four new dibenzo-24-crown-8 (DB24C8)-based ammonium-containing pseudorotaxanes, for which one of the two encircled axle's extremities consists of a perfluorobutyl moiety. The subsequent dethreading of the DB24C8 over the perfluorobutyl extremity was studied. Although the perfluorobutyl extremity of an ammonium-containing axle did not allow threading of DB24C8, dethreading of a perfluorobutyl extremity-containing pseudorotaxane was possible and its rate depended on both the strength of the template-to-DB24C8 complex and the nature of the axle. In particular, dethreading process may be assisted by the presence, in the threaded axle, of a poor secondary site of interaction for the DB24C8 and this assistance proved to be higher when this site is close to the DB24C8.

Synthesis of Isomeric Dinitro and Diamino Derivatives of Polycyclic Crown Ethers: Dibenzo-18-crown-6 and Dibenzo-24-crown-8

Specific features of the synthesis of polycyclic crown ethers dibenzo-18-crown-6 and dibenzo-24-crown-8 and their dinitro and diamino derivatives have been studied. A mixture of isomers of dibenzocrown ether derivatives was obtained and separated. The spectral and thermal characteristics of the synthesized compounds and the kinetics of synthesis of dibenzo-24-crown-8 by the two-component condensation of pyrocatechol with 1-chloro-2-[2-(2-chloroethoxy)ethoxy]ethane in an alcoholic medium in the presence of a KOH template agent were studied.

Directional molecular transportation based on a catalytic stopper-leaving rotaxane system

Ratchet mechanism has proved to be a key principle in designing molecular motors and machines that exploit random thermal fluctuations for directional motion with energy input. To integrate ratchet mechanism into artificial systems, precise molecular design is a prerequisite to control the pathway of relative motion between their subcomponents, which is still a formidable challenge. Herein, we report a straightforward method to control the transportation barrier of a macrocycle by selectively detaching one of the two stoppers using a novel DBU-catalyzed stopperleaving reaction in a rotaxane system. The macrocycle was first allowed to thread onto a semidumbbell axle from the open end and subsequently thermodynamically captured into a nonsymmetrical rotaxane. Then, it was driven energetically uphill until it reached a kinetically trapped state by destroying its interaction with ammonium site, and was finally quantitatively released from the other end when the corresponding stopper barrier was removed. Although the directional transportation at the present system was achieved by discrete chemical reactions for the sake of higher transportation efficiency, it represents a new molecular transportation model by the strategy of using stopper-leavable rotaxane.