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Formation of inclusion complexes involving a cavitand derivative (as host) and an antimetabolite drug, methotrexate (as guest) was investigated by photoluminescence measurements in dimethyl sulfoxide solvent. Molecular modeling performed in gas phase reflects that, due to the structural reasons, the cavitand can include the methotrexate in two forms: either by its opened structure with free androsta-4-en-3-one-17α-ethinyl arms or by the closed form when all the androsta-4-en-3-one-17α-ethinyl arms play role in the complex formation. Experiments reflect enthalpy driven complex formation in higher temperature range while at lower temperature the complexes are stabilized by the entropy gain.

Suzuki and Sonogashira coupling reactions of 3-iodo-2-phenylbenzofuran, leading to the corresponding 3-aryl- and 3-alkynyl derivatives, respectively, were carried out using a silica supported pyridinium ionic liquid based heterogeneous catalyst. Under optimized reactions conditions, arylboronic acids with either electron withdrawing or -donating substituents as well as terminal alkynes with aromatic or aliphatic groups could be coupled to the benzofuran skeleton efficiently. The application of this catalyst made it possible to carry out the reaction under phosphine-free and, in case of the Sonogashira coupling, under copper-free conditions. The catalyst retained its activity in at least 7 subsequent runs in both types of reactions. Palladium leaching of less than 1% of the original amount used in the catalytic reaction was observed under optimized conditions in most cases. The methodology was applied successfully in the synthesis of nine different 3-aryl- and ten different 3-alkynyl benzofuran derivatives in moderate to high yields.

A tetraiodocavitand, synthesised in conventional high‐yielding reactions, was used as substrate in homogeneous catalytic reactions such as aminocarbonylation and Sonogashira reaction. 3α‐Aminopregnane and 17α‐ethinylandrostane derivatives were used as coupling agents, respectively. While the aminocarbonylation of the tetraiodocavitand carried out at low pressure carbon monoxide resulted in the formation of tetra‐carboxamides as major products, the high pressure carbonylation (40 bar CO) yielded the corresponding tetrakis(2‐ketocarboxamides) with high chemoselectivity. The ethinyl functionality of the steroid enabled the facile cross‐coupling with the cavitand possessing iodoarene functionalities.

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