Monoribbed‐Functionalized Macrobicyclic Iron(II) Complexes Decorated with Terminal Reactive and Vector Groups: Synthetic Strategy, Chemical Transformations and Structural Characterization

Abstract

Comprehensive SummaryGeneral and straightforward synthetic strategy towards the iron(II) clathrochelates with functionalizing substituents in their apical capping and one of the three chelate ribbed fragments was developed. Their hexachloroclathrochelate precursors were prepared by the direct template condensation of dichloroglyoxime with a suitable boronic acid on the Fe2+ ion as a matrix and underwent a stepwise nucleophilic substitution with S2‐, N2‐ or O2‐bis‐nucleophiles, forming the alicyclic or aromatic N2‐, S2‐ or O2‐six‐membered fragments. Depending on the reaction conditions and precursor‐to‐dinucleophile molar ratios, iron(II) clathrochelates with one (S, O and N), two (S, O and N) or three (S and O) X2‐six‐membered ribbed substituent(s) were obtained. Their reactivity substantially decreases in a row: Cl6‐Cage > Cl4X2‐Cage (where X = S, O or, especially, N) > Cl2X4‐Cage (where X = S or O). The reactive monoribbed‐functionalized clathrochelates underwent further chemical transformations giving the target macrobicyclic complexes with terminal vector groups. As follows from the single crystal XRD data, their FeN6‐coordination polyhedra possess the geometry intermediate between a trigonal prism and a trigonal antiprism (φ = 21.3°—25.20°). Fe—N distances vary from 1.887(6) to 1.933(8) Å. Their 3D‐molecules, the hydrophobic–hydrophilic balance in which can be tuned using a ribbed functionalization, form in the crystals the intermolecular specific halogen bonds and/or hydrophobic interactions.