Self-inclusion properties of C60-linked calix[5]arene

C₆₀-linked calix[5]arenes were synthesized and their intramolecular binding properties were investigated. The self-inclusion ratio of the C₆₀ moiety was determined by using UV-vis spectroscopy, and the ratio depends on chain length, temperature, and solvent. Influence of temperature and solvent was explained by the thermodynamic data of the intramolecular complex formation process.     

Synthesis of Chemical Modified β-cyclodextrin and its Inclusion Behavior in Alcohol/Water Mixed Solvents

Abstract

The chemical modified β-cyclodextrin(CD), which bears a fluorophore group — N,N-dimethylamino-chalcone (DMAC), was synthesized. The self-inclusion behavior of this compound in aqueous solution and in alcohol/water mixed solvents was investigated in detail, and compared with the inclusion system of non-modified CD with free DMAC molecule. The results showed that a deep self-inclusion complex was formed for this compound in aqueous solution and had the ability to recognize different organic molecules by two fully different modes: “in-out” and “co-inclusion” mechanisms. The inclusion behavior of these systems in various ratio of alcohol/water mixture as solvents was investigated. The results indicated that the self-inclusion complex has a higher stability in alcohol/water mixed solvents than that in the case of non-modified CD. The chalcone group appended at β-CD enabled the host as a sensitive probe to study the inclusion behavior of CD.     

Synthesis of resorcin[4]arene bearing self-folding substituent

Thiomethylation of resorcin[4]arene using N,N-diisopropyl-2-aminoethanethiol hydrochloride and formaldehyde [1:4:4 molar ratio] carried out in methanol/acetic acid [1:1 v/v] at 60 °C produced monofunctionalized product 3 in 68% yield. The introduced substituent was intramolecularly self-included into the cavity. This self-inclusion reduced the reactivity of the aromatic rings and inhibited further functionalization.     

Synthesis of a singly bridged resorcinarene-dimer by Mannich reaction with N,N′-diethylethylenediamine and formaldehyde: self-inclusion of bridging diazahexamethylene unit in methanol

Mannich reaction of resorcin[4]arene with N,N′-diethylethylenediamine and formaldehyde produced a singly bridged resorcinarene-dimer bearing sixteen hydroxyl groups at their peripheral positions, which exists in a closed capsular conformation including the diazahexamethylene bridge chain between the two resorcinarene units in CD₃OD.