A gram-scale synthesis, physico-chemical characterization, and lead-likeness assessment of 4-di/trifluoromethyl-2-heterabicyclo [2.1.1]hexanes as fluorinated bicyclic proline analogues and phenyl isosteres are disclosed. The key step of the synthesis included iodocyclization of fluorinated 3-hydroxy-/3aminomethyl methylenecyclobutanes; with the amino derivatives, the reaction was accompanied with carboxylation and further cyclization. Apart from the corresponding 4-di/ trifluoromethyl-2,4-methanoprolines, a series of fluorinated oxabicyclo[2.1.1]hexane-derived building blocks relevant to medicinal chemistry (i. e. primary iodides, carboxylic acids, alcohols, azides, primary amines, sulfonyl chlorides, and alkynes) were prepared. For representative derivatives of the resulting fluorinated 2-oxabicyclo[2.1.1]hexanes, pK a and logP values were measured to clarify their potential as the possible phenyl isosteres. Apart from the somewhat increased acidity, finetuned lipophilicity intermediate between that of non-fluorinated or aromatic counterparts was observed. Finally, the potential of the title building blocks was demonstrated by generation of virtual compound libraries using the LLAMA software. The resulting libraries fitted perfectly the lead-like chemical space, had higher three-dimensionality, and showed lower mean lead-likeness penalty as compared to those obtained from either non-fluorinated or aromatic derivatives.

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By employing the methods of molecular mechanics, semi-empirical quantum-chemical РМ3 and Monte-Carlo, the positioning of monocyclopentadienylferrum (II) molecules in double-walled (5,5)@(10,10) carbon nanotubes (CNT) depending on their concentration and temperature has been studied. The molecules have been found out to form stable bonds with CNT walls, with a tendency between intercalate stability and the CNT structure. The temperature growth (over ~500 K) causes gradual bond ruining followed by extrusion of interwall intercalate. Further temperature increase up to 600–700 K is characterised with intercalate external surface desorption, stabilising the whole system and keeping the interwall intercalate only. The CNT’s UV-spectrum (5,5)@(10,10) depending on the intercalate concentration and association constant of the “double-walled CNT–intercalate” system have been calculated. A combination of unique optical, electrical and magnetic behaviour of cyclopentadienyl complexes with their ability to form high-stable intercalate with CNT opens a prospect of their applying in nanotechnology.

The positioning of tricarbonyl(cyclopentadienyl)manganese molecules in double‐walled (5.5)@(10.10) carbon nanotubes depending on their concentration and temperature was studied using the methods of molecular dynamics, semi‐empirical quantum‐chemical parameterized model number 3 and Monte‐Carlo. The molecules were found to form stable bonds with the carbon nanotubes walls, with a tendency between intercalate stability and the carbon nanotubes structure. A temperature increase (above ˜460 K) causes gradual bond ruining followed by extrusion of interwall intercalate. Further temperature increase up to 600–750 K is characterised with intercalate external surface desorption, stabilising the whole system and keeping the interwall intercalate only. Double‐walled carbon nanotubes UV‐spectra depending on the intercalate concentration and association constant of the “double‐walled carbon nanotubes‐intercalate” system were calculated. A combination of unique optical, electrical and magnetic behaviour of cyclopentadienyl complexes with their ability to form high‐stable intercalate with carbon nanotubes opens a prospect of their application in nanotechnology.