Structural chemistry of complexes with an encapsulated metal ion. α-Dioximate, oximehydrazonate, and dihydrazonate clathrochelates

Abstract

The review surveys the main trends in the structural chemistry of clathrochelates: the determination of the crystal and molecular structures of various types of new complexes, their symmetry and functionality; the supramolecular organization and phase transitions of clathrochelate crystals; the structure-spectral parameter relationships and the deduction of the molecular structures; the use of X ray diffraction data for explanation of the kinetic and thermodynamic parameters of the synthesis and decomposition of clathrochelates.

Synthesis, X-Ray Structure and (Spectro)electrochemical Study of an Electrochromic Iron(II) Chlathrochelate with Tuned Redox Properties

“…The average j value of 20.5°, as well as the height h of this polyhedron (2.35 Å), are characteristic of the boron-capped iron(II) tris-dioximates. [30] Fe-N distances in this molecule are slightly nonequivalent and fall within the range 1.917(3)-1.924(3) Å for its a-benzildioximate fragments and are close to 1.90 Å for the functionalized chelate cycle with the annulated dimethylquinoxaline heterocycle. The C-C bonds in this heterocyclic substituent show an expressed alternation reference electrode were used.…”

“…Main C=N, N-O and B-O bond lengths as well as the corresponding bond angles in a clathrochelate framework are characteristic of the boron-capped iron(II) tris-dioximates. [29,30] The molecular structure of the clathrochelate FeBd 2 (Me 2 QnGm)(BF) 2 in solution was confirmed using one-dimensional (1D) and two-dimensional (2D) 1 H and 13 C{ 1 H} NMR spectra; the assignment of the signals in these spectra is shown in Figure 2. These NMR data were found to be in an excellent agreement with the above single-crystal X-ray diffraction data.…”

New o-carboranyl-containing capping agents for d-metal tris-dioximates and first bis-C-carboranylboron-capped iron(II) clathrochelates: Synthesis and X-ray structure

“…This conclusion was confirmed by the direct X-ray crystallography experiment for complex 5b [26]. According to the X-ray data, the main distances in the macrobicyclic framework of 5b (Table 1) are characteristic of the clathrochelate iron(II) tris-dioximates [27][28][29]. The height h of the coordination polyhedron is approximately 2.35 Å and the average bite angle a (half the chelate N-Fe-N angle) is equal to 39.2°.…”

Using Minisci Reaction for Modification of the tris-Dioximate Metal Clathrochelates: Free-Radical Substitution at the Glyoximate Fragment of an Iron(II)-Encapsulating Cage Framework

“…Other main bond lengths and angles in the macrobicyclic framework and those in the rib 1,4-dioxan-2-yl substituent have usual values. [22,23] This substituent adopts 2 (where R are 1,4-dioxan-2-yl, tetrahydrofuran-2-yl or 1,3-dioxolan-2-yl substituents) reported in literature [10,11,13] and the clathrochelate under study are crystallized in this chiral space group, independently on the nature of a monofunctionalized cage molecule (i.e. is it chiral or not).…”