On a way to new types of the polyfunctional and polytopic systems based on cage metal complexes: Cadmium-promoted nucleophilic substitution with low-active nucleophilic agents

Two alternative approaches to modification of a cage complex: nucleophilic substitution and electrophilic addition for the synthesis of an iron(II) clathrochelate with an annulated imidazole fragment

“…The comparison of the MLCT bands of FeBd 2 Cl 2 Gm(BF) 2 (Fig.2, a) and FeBd 2 (Im(Ph)Gm)(BF) 2 (Fig.2, b) showed the transition from two bands of comparable intensity (460 -470 nm, ε ∼ 1.0 -1.5 · 10 4 mol -1 L cm -1 ) to one major band (500 nm, ε ∼ 2.5 · 10 4 mol -1 L cm -1 ) and two minor bands (520 -540 nm, ε ∼ 2 -4 · 10 3 mol -1 L cm -1 ), so a substantial red shift occurred. However, the difference in the optical spectra of FeBd 2 (Im(Ph)Gm)(BF) 2 and FeBd 2 ((NH 2 ) 2 Gm)(BF) 2 is less pronounced, the absorption of the latter in the visible range being determined by the band at 520 nm [15]. CVA examination of the clathrochelate FeBd 2 (Im(Ph)Gm)(BF) 2 showed no ligandcentered redox waves from -1200 +400 mV (vs 0.01 M Ag + /Ag 0 ).…”

“…[2][3][4] [10]. Somewhat later, a synthetic approach to homolytic formation of new C-C bonds at the clathrochelate ribs was developed (Scheme 1, b) [11][12][13][14] A third synthetic alternative to the ribbed clathrochelate modificationelectrophilic addition (Scheme 1, c) -has been studied quite scarcely; only one publication is currently available in the literature [15].…”

The molecular design of cage metal complexes for biological applications: pathways of the synthesis, and X-ray structures of a series of newN2-,S2- andO2-alicyclic iron(ii) di- and tetrachloroclathrochelates

“…However, this synthetic approach can be performed under vigorous reaction conditions only for several types of a-dioximes and only for fluoroboron-capped cage complexes. The bis-abenzildioximate mono-and dihalogenoclathrochelates of this type have been recognized as the most suitable reactive macrobicyclic precursors of the above biological effectors: they easily undergo well-known classical organic reactions, such as N,O,S,C,Pnucleophilic substitution 12,13,[17][18][19][20][21][22] (including cadmium-promoted reactions with low-active nucleophiles 21,22 ), free-radical substitution, [23][24][25][26][27][28] copper-promoted cyanation, 29 electrophilic addition (for their amine derivatives 30,31 ), and copper(0)-and copper(I)-promoted reactions of halogen exchange, 32 reductive homocoupling, 6,33 and hydrodehalogenation. 29,33 However, the apical functionalization of these fluoroboron-capped halogenoclathrochelate precursors, allowing tuning the physical properties of their macrobicyclic derivatives (in particular their solubility in water or biological media), and performing their efficient binding to a given biological target, is hardly possible (or even impossible).…”

ESI-MS Study of Ionization Pathways and Cation-Receptor Properties of the Iron(II) Mono- and Bis-Clathrochelates

“…[29][30][31] We thus aimed on studying cation-receptor properties of halogen-containing iron(II) mono-and bis-clathrochelates (Scheme 1) having from two (FeBd 2 (Cl 2 Gm)(BF) 2 , FeBd 2 (Br 2 Gm)(BF) 2 , FeBd 2 (I 2 Gm) (BF) 2 , {FeBd 2 (BrGm)(BF) 2 } 2 and {FeBd 2 (IGm)(BF) 2 } 2 ) to six (Fe(Cl 2 Gm) 3 (Bn-C 4 H 9 ) 2 ) chlorine atoms in their chelate α-dioximate fragments. Note that these reactive compounds have been earlier recognized as convenient macrobicyclic precursors for their further functionalization with N,O,C,Snucleophiles [3,24,27,[29][30][31][32][33][34][35][36][37][38] (including those with ionophoric, pharmacophoric and fluorophoric groups), and for the design of hybride and multicentered compounds. [24,27,28] Here we also describe the cation-receptor properties of their dimethyl-and diamine-containing clathrochelate analogs FeBd 2 Dm(BF) 2 …”