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This short review is devoted to asymmetric phase-transfer reactions that employ hybrid ammonium Cinchona catalysts supported by possessing hydrogen-bond donor groups. We present recent advances utilizing this type of catalyst in the field of biphasic reaction systems. The main emphasis is placed on the advantages of additional functional groups present in the structure of the catalyst, such as hydroxy, amide, (thio)urea or squaramide. 1 Introduction 2 Phase-Transfer Hybrid Cinchona Catalysts with a Free Hydroxy Group 3 (Thio)urea Hybrid Cinchona Catalysts 4 Hybrid Amide-Based Catalysts Bearing a Cinchona Scaffold 5 Conclusions [ABSTRACT FROM AUTHOR]

Herein we present the synthesis and association analysis of a new family of "pincer" receptors containing units of stable 26-membered tetraamidic macrocyclic scaffolds in their structures. These units, linked by aliphatic or aromatic chains, are capable of binding an anionic guest due to the presence of amide functions playing the role of hydrogen bond donating systems. Such neutral receptors show strong binding properties with respect to dicarboxylate anions. Despite the discovery that we observed a complexed, mixed binding model in all the systems tested, we can infer that the receptor region to which the guest chain is associated depends on the latter's length. [ABSTRACT FROM AUTHOR]

Some of 19-membered unclosed cryptands were recognized as chiral species in a solid state. While, in terms of 20-membered macrocycle, we tune the lariat arm, developing the synthesis of α- and β-naphthyl terminated moieties to gain the structural control over chirality phenomena of these systems. Indirect synthetic approach delineates the way to reach both target structures. Solely, macrocycle functionalized with the β-naphthyl group is capable of desirable interactions with the frame of entity inducing its stronger bending that leads to the chiral crystals formation. Their structural features were examined by single crystal X-ray diffraction and chiroptical method, represented by ECD/UV spectroscopy. [ABSTRACT FROM AUTHOR]