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New chiral monoaza-15-crown-5 type macrocycles annelated to methyl 4,6-O-benzylidene-α-D-galactopyranoside have been synthesized. These crown ethers proved to be efficient catalysts in a few asymmetric reactions under mild phase transfer catalytic conditions. Michael adducts were formed with good to excellent enantioselectivities, so the addition of diethyl acetamidomalonate to β-nitrostyrene took place with up to 92% ee, while the reaction of diethyl acetoxymalonate with chalcones proceeded with up to 99% ee. Using diethyl bromomalonate as the nucleophile, the chiral cyclopropane derivatives were formed in up to 99% ee with the addition to chalcone, in up to 78% ee in the reaction with benzylidene malononitrile, and in up to 76% ee in the reaction with 2-benzylidene-1,3-diphenyl-1,3-propanedione applying α-D-galactoside-based crown ethers as the catalysts. In the Michael addition, the substituents of the chalcone had a considerable impact on the outcome of the reactions. Quantum chemical calculations have also been employed to evaluate the origin of the stereoselectivities.

The stereochemistry of calix[4]arenes capped by diamide bridges in the 1,3-position on the lower rim was established by 1H and 13C solution and solid state NMR. The 13C chemical shifts of Artext-decoration:underline'CH2Ar were found to be diagnostic of the cone, partial cone and 1,3-alternate conformations also in the solid state. Two sets of signals appearing in the CP/MAS spectra of 1,3-alternate and partial cone compounds indicate that these molecules occupy inequivalent sites in the elemental cell.

The interactions between a calixarene host comprising dissociable protons, and an organic dye guest existing in a neutral base and in a protonated form, have been studied on model systems obtained by dissolving Nile Blue base (1) and tetraundecylcalix[4]resorcinarene (2) in two apolar solvents, dichloromethane and toluene. Steady state absorption and fluorescence spectroscopy and fluorescence lifetime measurements were applied as experimental methods. It has been established that the equilibrium composition of these systems is controlled predominantly by three reactions: (1) formation of the weakly bound complex 1·2; (2) simultaneous formation of the tightly bound ionic species with zero net charge 1+·2− (1+ = protonated form of 1, 2− = monophenolate form of 2); (3) protonation of the latter product in a subsequent step yielding 1+·2. The equilibrium constants for these reactions have been determined from the absorption spectra by an iterative procedure. The high value of the equilibrium constant for reaction (2) in toluene (9.8 × 106) is in accordance with the strongly solvatophobic nature of cation 1+ in this solvent. The fluorescence lifetime of neutral base 1 increases whereas that of its protonated form, 1+, markedly decreases upon complexation. These effects have been interpreted in terms of intra- and intermolecular decay channels.