First “Click” Synthesis of the Ribbed‐Functionalized Metal Clathrochelates: Cycloaddition of Benzyl Azide to Propargylamine Iron(II) Macrobicycle and the Unexpected Transformations of the Resulting Cage Complex

Abstract

A bis(propargylamine) iron(II) cage complex was obtained in high yield by nucleophilic substitution of reactive chlorine atoms of its dichloroclathrochelate precursor with an excess of propargylamine in acetonitrile. The macrobicyclic product undergoes copper(I)‐catalyzed “click” reaction with benzyl azide giving the copper(II)‐containing complex of the bis(benzyl‐1,2,3‐triazolylmethylamine) clathrochelate ligand: the Cu2+ ion coordinates two deprotonated amino groups and two donor azaheterocyclic fragments of the ribbed substituents of the macrobicyclic ligand. Demetallation of this copper(II) complex with potassium cyanide gave target clathrochelate as a minor product. The major macrobicyclic product of this demetallation containing one inherent amino group and one benzyl‐1,2,3‐triazolylmethylamine ribbed substituent resulted from the side dealkylation reaction. The complexes obtained were characterized using elemental analysis, MALDI‐TOF mass spectrometry, IR, UV/Vis, 1H and 13C{1H} NMR spectroscopy, and by X‐ray diffraction. The geometry of their FeN6 coordination polyhedra is intermediate between a trigonal prism and a trigonal antiprism.

Synthesis and Structure of the Bis- and Tris-Polyhedral Hybrid Carboranoclathrochelates with Functionalizing Biorelevant Substituents—The Derivatives of Propargylamine Iron(II) Clathrochelates with Terminal Triple C≡C Bond(s)

“…In order to avoid formation of the complexes {Cu 2 (µ-C≡CR) 2 }, which are reported [33,34] to give the acetylene dimerization products in the presence of air oxygen, the "click" reactions under study were performed in an inert atmosphere (under argon). We also performed the analogous double-"click" reaction by Scheme 5 of a known [35] dipropargylamine iron(II) clathrochelate 16 as a bifunctionalmacrobicyclic precursor with two terminal C≡C bonds.…”

“…In order to avoid formation of the complexes {Cu2(μ-C≡CR)2}, which are reported [33,34] to give the acetylene dimerization products in the presence of air oxygen, the "click" reactions under study were performed in an inert atmosphere (under argon). We also performed the analogous double-"click" reaction by Scheme 5 of a known [35] dipropargylamine iron(II) clathrochelate 16 as a bifunctionalmacrobicyclic precursor with two terminal C≡C bonds. The obtained complexes were characterized using elemental analysis, MALDI-TOF mass, UV-Vis, 1 H, 1 H{ 11 B}, 11 B, 11 B{ 1 H}, 19 F{ 1 H} and 13 C{ 1 H}-NMR spectra, and also by a single crystal X-ray diffraction experiment (for the hybrid diethylamine-functionalized carboranoclathrochelate 15).…”

Iron(II) Clathrochelate with Terminal Triple C≡C Bond and Its Carboranoclathrochelate Derivative with a Flexible Linker between the Polyhedral Cages: Synthesis and X‐Ray Structure

“…The N–H bond in the molecule 2 is parallel to the N–O bond on the same ribbed α‐dioximate fragment. In contrast to the earlier reported dipropargylamine iron(II) clathrochelate, this amine‐containing chelate fragment does not form the strong hydrogen bonds, while its N–H…π and N–H…H–C interactions were observed in the X‐rayed crystal of 2 . The N–H bond in the molecule 2 is parallel to the N–O bond on the same ribbed α‐dioximate fragment.…”

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 …”