For the first time a series of new cationic amphiphilic p-tert-butylthiacalix[4]arene derivatives adopting 1,3-alternate stereoisomeric form was synthesized by quaternization of several tertiary amines and N-heterocycles. The structure of all products was well-defined using modern physical technics. The influence of calixarene and amine sterical hindrances on reactivity is discussed.

Herein we report the first example of amphiphilic PdII–NHC complexes on the thiacalix[4]arene backbone in 1,3‐alternate configuration. Relative catalytic activity of synthesized PdII–NHC complexes in Suzuki–Miyaura coupling of haloarenes with phenylboronic acid was studied. A combination of micellar and metallocomplex catalysis was observed in Suzuki–Miyaura coupling upon going from pure DMF to water/DMF 3:1: the 2‐fold increase of conversion of 4‐bromoanisole unlike pure DMF was found. Interesting feature was found using chloroarene in DMF/water: the reaction selectivity changed from heterocoupling to homo coupling of phenylboronic acid. PdII–NHC complexes demonstrated a high activity in model hydrogenation reaction of p‐nitrophenol using sodium borohydride. The most lipophilic PdII–NHC complex was found to be most active, which can be attributed with additional p‐nitrophenol preconcentration in the aggregates due to larger hydrophobic capacity of macrocycle.

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New water-soluble derivatives of p-tert-butylthiacalix [4]arene have been synthesized in the stereoisomeric form 1,3-alternate with butyl and tetradecyl groups on one side of the macrocyclic platform and tri/tetraethylene glycol substituents on the other. The aggregation characteristics of macrocycles in the aquatic environment (CAC, aggregate size, zeta potential) have been studied. It has been demonstrated that the resulting aggregates have the ability to solubilize the lipophilic azo dye Orange OT, and the solubilizing ability significantly increases on going from butyl to tetradecyl derivatives. Using the methods of dynamic and electrophoretic light scattering and fluorimetry with ethidium bromide as a probe, it was shown that the obtained macrocycles interact with the DNA of the calf thymus. It was found that the efficiency of the interaction is greatly influenced by the length of the oxyethyl fragments: macrocycles containing tetraethylene glycol fragments are more effective than triethylene glycol analogs, causing a 2-fold compaction of DNA.

The possibility of one-pot synthesis of mono-substituted quaternized derivatives of p-tert-butylthiacalix [4]arene was demonstrated for the first time by the reaction of distally di-bromopropyl substituted p-tert-butyl thiacalix [4]arene with several nitrogen-containing nucleophiles. The structure and composition of the reaction products were analyzed by modern physical methods, including two-dimensional NMR spectroscopy and high-resolution mass spectrometry. A detailed analysis of the reaction mixtures made it possible to reveal the dealkylation mechanism, which consists in the nucleophilic attack of the bromide ion on the O-CH 2 carbon atom, followed by the formation of a brominecontaining adduct, detected by mass spectrometry. Dealkylation does not occur when the classical di-bromopropyl substituted p-tert-butyl calix [4]arene is used as a substrate -the bis-quaternized imidazolium calix [4]arene salt is formed in a high yield. Such a difference in the reactivity of two macrocycles is associated with the difference in the sizes of the macrocycles: in the case of di-substituted thiacalixarene, which has a large size, two unsubstituted hydroxyl groups form a hydrogen bond with only one alkoxy group, while in the classical calix [4]arene, two paired hydrogen bonds are formed. As a result, one of the two alkoxy groups of the thiacalixarene is more accessible for nucleophilic attack; formed thereafter thiacalixarene nucleofuge-anion is stabilized by two hydrogen bonds at once.