Antioxidant properties of mono- and dihydroxyphenolic acids and their alkyl esters were examined, with emphasis on the relationship between their molecular structure and antioxidant activity. Test media with different tocopherol level were used for determining the oxidative stability: original refined sunflower oil (total tocopherols 149.0 mg/kg), partially tocopherol-stripped sunflower oil (to...

The binding behaviour of differently substituted diamide axle molecules to Hunter/Vögtle tetralactam macrocycles was studied with a combination of NMR titration, isothermal titration calorimetry (ITC) experiments and calculations employing density functional theory (DFT), along with dispersion-corrected exchange-correlation functionals. Guests with alkyl or alkenyl chains attached to the diamid...

The synthesis and thermal properties of new shape-persistent macrocycles of different sizes decorated with intraannular alkyl chains are described. The alkyl chain length is in all cases sufficient to cross the rings and to fill their interior completely. The investigation of the thermal behavior has shown that the smaller cycles do not exhibit thermotropic mesophases. Single crystal x-ray anal...

Different enamines were introduced at the meso position of the BODIPY by catalyst free oxidation of tert-amines and in situ cross coupling with 8-chloro BODIPY. The reaction conditions were optimized to achieve better yields. The reaction works well with aliphatic tert-amines bearing an N-(CH-CH-) backbone. The N-alkyl substituents perturb the optical properties of enamine substituted BODIPYs.

[reaction: see text] Enantio- and diastereoselective syntheses of trans-2,5-disubstituted morpholine derivatives are described. The routes are initiated by the reaction of enantiopure epoxides (2) with amino alcohols (3) and address the problem of regioselective hydroxyl activation-ring closure of the resulting amino diol adducts for (amino alcohol-derived) alkyl substituents of different steri...

m-Phthalic diamide-linked zinc bisporphyrinates have been developed as chirality probes for monoamines. They are capable of determining the absolute configuration of monoamines and distinguishing between alkyl and aryl substituents of chiral monoamines. Our studies suggest that steric interactions play critical roles in the molecular recognition process.

Diaryliodonium salts are demonstrated as efficient arylating agents of aliphatic alcohols under metal-free conditions. The reaction proceeds at room temperature within 90 min to give alkyl aryl ethers in good to excellent yields. Aryl groups with electron-withdrawing substituents are transferred most efficiently, and unsymmetric iodonium salts give chemoselective arylations. The methodology has...

Postsynthetic covalent modification of metal-organic frameworks (MOFs) with long alkyl substituents is shown to protect these materials against moisture. These MOFs, which normally display hydrophilic properties, are readily converted into hydrophobic or superhydrophobic materials. Overcoming the inherent sensitivity of MOFs to water represents a major step forward in their widespread use in te...

A new type of TfOH-catalyzed tandem cyclopropane ring enlargement/C-C formation/etherification reaction between alkynylcyclopropanes and 1,3-diketones to cyclobutane-fused dihydrofurans is described. The reaction tolerates a range of aryl and alkyl substituents with moderate to good yields.