Search results for "jodi"
showing 10 items of 26 documents
Iodination of antipyrine with [N–I–N]+ and carbonyl hypoiodite iodine(i) complexes
2023
A series of iodine(I) complexes, both known and new, were synthesised and the dependence of iodination reactivity on the identity of the Lewis bases and anions present was investigated. Using a previously established screening protocol based on the iodination of antipyrine to iodo-antipyrine, the capability of the iodine(I) species to perform the iodination was tested and compared, especially in relation to Barluenga's reagent, [I(pyridine)2]BF4. The results indicated that the identity of both the Lewis bases and the anion influence the iodination capability of the iodine(I) species, and that the less efficient reagents can deliver favourably comparable percentage conversions with longer re…
Carbonyl hypoiodites from pivalic and trimesic acid and their silver(I) intermediates
2022
The first tris(O–I–N) carbonyl hypoiodites have been synthesised based on trimesic acid and pyridine or 4-methylpyridine, with their structures definitively confirmed by single crystal X-ray diffraction (SCXRD). The more soluble carbonyl hypoiodites based on pivalic acid have also been studied via NMR, SCXRD, and computational analyses, enabling the study of the direct silver(I) precursor and intermediates of the resulting carbonyl hypoiodites generated using a range of substituted pyridines. peerReviewed
Halogen-Bonded [N–I–N]− Complexes with Symmetric or Asymmetric Three-Center–Four-Electron Bonds
2023
A series of LH[Z–I–Z] halogen(I) complexes, where Z = saccharinato or phthalimido anions and LH = pyridinium, pyrazinium, tetrabutyl (TBA)- or tetramethylammonium (TMA) cations, were prepared, structurally characterized, and discussed as complexes consisting of a [N–I–N]− anion with a three-center–four-electron (3c-4e) halogen bond, and a hydrogen-bonding (pyridinium or pyrazinium) or inert (TBA or TMA) cation. The symmetric [N–I–N]− anion, reminiscent of the triiodide [I–I–I]− anion, is found to be structurally equivalent to its cationic analogue [N–I–N]+ with N–I bond lengths of 2.26 Å. In contrast to the homoleptic [N–I–N]+ complexes, asymmetry of the N–I bond lengths (2.21 and 2.28 Å) w…
Macrocyclic complexes based on [N⋯I⋯N]+ halogen bonds
2021
New 1–2 nm macrocyclic iodine(I) complexes prepared VIA a simple ligand exchange reaction manifest rigid 0.5–1 nm cavities that bind the hexafluorophosphate anion in the gas phase. The size of the cavities and the electrostatic interactions with the iodine(I) cations influence the anion binding properties of these macrocyclic complexes. peerReviewed
Ligand exchange among iodine(I) complexes
2022
A detailed investigation of ligand exchange between iodine(I) ions in [N⋯I⋯N]+ halogen-bonded complexes is presented. Ligand exchange reactions were conducted to successfully confirm whether iodine(I) complex formation, via the classical [N⋯Ag⋯N]+ to [N⋯I⋯N]+ cation exchange reaction from their analogous Ag+ complexes, could be determined solely by using 1H NMR spectroscopy. In instances where the formation of the iodine(I) complex was unclear or in low yield by the traditional cation exchange reaction, a ligand exchange reaction was used to form the desired iodine(I) complexes in a quantitative manner. Mixing two homoleptic [N⋯I⋯N]+ iodine(I) complexes in 1 : 1 ratio was found to undergo a…
Halogen-Bonded Mono-, Di-, and Tritopic N-Alkyl-3-iodopyridinium Salts
2023
Halogen bonding interactions of 15 crystalline 3-iodopyridinium systems were investigated. These systems were derived from four N-alkylated 3-iodopyridinium salts prepared in this study. The experimental results in the solid state show that halogen bonding acts as a secondary intermolecular force in these charged systems but sustains the high directionality of interaction in the presence of other intermolecular forces. Halogen bonds donated by polytopic 3-iodopyridinium cations are also sufficient to enclose guest molecules inside the formed supramolecular cavities. The experimental data were supplemented by computational gas-phase and solid-state studies for selected halogen-bonded systems…
Iodine Clathrated : A Solid-State Analog of the Iodine-Starch Complex
2019
Co-crystallizing iodine with a simple dicationic salt (1,8- diammoniumoctane chloride) results in the clathration of the iodine (I2) molecules inside trigonal and hexagonal helical channels of the crystal lattice with 72 wt% overall I2 loading. The I2 inside the bigger trigonal channel forms a I-I•••I-I•••I-I halogen-bonded infinite helical chain, while the I2 in the smaller hexagonal channel is disordered. In both channels the I2 interaction with the channel wall happens through I-I•••Cl- halogen bonds. The helical channels in the crystal lattice are constructed via the strong charge-assisted H2N+ -H•••Cl- hydrogen bonds between the dications and the chloride anions. The structure shows a …
Charge-Assisted Halogen Bonding in an Ionic Cavity of a Coordination Cage Based on a Copper(I) Iodide Cluster.
2023
The design of molecular containers capable of selective binding of specific guest molecules presents an interesting synthetic challenge in supramolecular chemistry. Here, we report the synthesis and structure of a coordination cage assembled from Cu3I4– clusters and tripodal cationic N-donor ligands. Owing to the localized permanent charges in the ligand core the cage binds iodide anions in specific regions within the cage by ionic interactions. This allows the selective binding of bromomethanes as secondary guest species within cage promoted by halogen bonding, which was confirmed by single crystal X-ray diffraction. peerReviewed
Dimeric iodine(i) and silver(i) cages from tripodal N-donor ligands via the [N–Ag–N]+ to [N–I–N]+ cation exchange reaction
2022
The directionality of the [N–I–N]+ halogen bond makes iodine(I) ions impeccable tools in the design and construction of [N–I–N]+ halogen-bonded assemblies. The synthesis of dimeric iodine(I) cages with imidazole-derived N-donor tripodal ligands is described, as well as their corresponding silver(I) precursors. The addition of elemental iodine to the parent two-coordinate Ag(I) complexes produces iodine(I) complexes with three-center four-electron (3c–4e) [N–I–N]+ bonds. Complex formation via this cation exchange was confirmed by 1H and 1H–15N HMBC NMR studies in solution, and additionally by electrospray ionisation and ion mobility mass spectrometry analysis (MS) in the gas phase. The struc…
Do 2-coordinate iodine(I) and silver(I) complexes form Nucleophilic Iodonium Interactions (NIIs) in solution?
2022
The interaction of a [bis(pyridine)iodine(I)]+ cation with a [bis(pyridine)silver(I)]+ cation, in which an iodonium ion acts as nucleophile by transferring electron density to the silver(I) cation, is reinvestigated herein. No measurable interaction is observed between the cationic species in solution by NMR; DFT reveals that if there is an attractive interaction between this complexes in solution, it is dominantly the π-π interaction of pyridines peerReviewed