Iodine-containing charge transfer complexes

Torrance obtained a sample that showed ferromagnetic properties with a high Curie temperature by a reaction of 1,3,5-triaminobenzene with iodine under rather drastic conditions (Torrance et al., 1987). A charge-transfer complex of iodine with an aniline-black-type polymer [32], a heteroatom-containing analogue to [14 ] (Johannsen et al., 1989), may have been... 

LB film prepared from stearic acid and containing TBTTF-Zn(dmit)2 charge transfer complex (and oxidized by iodine exposure) Absorption, FTIR spectroscopy, lowangle X-ray diffraction, conductivity measurements Maximum conductivities perpendicular and parallel to the LB film were determined to be 10-3Scm-t and4.3xl0 l Scm-1 122... 

The charge-transfer complex of 1,4,7-trithiacyclononane 10 and I2 has been prepared by slow evaporation of solutions containing I2 and thioether macrocycle in CH2CI2. The structure of the complex showed two independent macrocycles in the asymmetric unit which are linked by a diiodine bridge. Asymmetric units are linked by iodine-iodine and sulfur-iodine interactions to form an extended array of linked macrocycles. The formation enthalpy ( AH = 35.0 kj mob1) and formation constant (K= 169 dm3 mol-1) of 1 1 adduct have been determined by electronic spectroscopy and compared to other polythia macrocycles of different sizes <1997JCD1337>. 

Very stable complexes, which may be sublimed and sometimes recrystallized, are obtained when the preparation of some phenothiazines by thionation is carried out using excess of iodine and sulfur. These complexes contain two, four, or six atoms of sulfur per phenothiazine residue, and their IR spectra are identical to those of the heterocyclic component, as expected of charge-transfer complexes. ... 

Nonaiodides are very rare, but two, as [l Me2PhN]+ and [K([15]ane05)]+ salts, have been structurally characterized. The anion in the former contains 14-membered rings tied by two iodine bridges into 10-membered rings, while that in the latter is best described as an [I3 (12)3] charge-transfer complex. 

A volume of the extract containing 0.05 to 0.15 mg of alkaloid was mixed with mM iodine in dichloroethane (1 ml). This mixture was diluted to 10 ml with dichloroethane. The extinction of the charge transfer complex at the maximum at 280 nm or 295 nm was measured against a reagent blank. The procedure has been successfully applied to atropine, hyos-cyamine, scopolamine, homatropine and their N-butyl analoges (94). 

A. Iodine The universal detection reagent iodine is used either as a 1% alcoholic spray, or the plate is placed in a closed jar or tank containing iodine crystals. The iodine vapor dissolves in, or forms weak charge-transfer complexes with organic compounds, which show up as brown spots on a pale yellow background within a few minutes. After marking zones for future reference, exposure of the plate to air causes the iodine to sublimate and the spots to fade, after which the plate can be sprayed with another reagent or the solute can be eluted from the plate for further analysis. 

When di-iodine reacts with heterocycles like thioamides or selonoamides new charge transfer complexes containing iodine are obtained [1-10], Various types of such complexes have been obtained thus far, including so called spoke or extended spoke structures (DS 1 or DS l -1 ) (D is the hgand donor) [1], Also iodine coordinated to two thioamides to form iodonium salts ([DS-I-DS] (Ij) )... 

Spectroscopic analysis has demonstrated that many nitrogen-containing heterocyclic dmgs form charge transfer complexes with iodine [15, 16]. UV-spectrophotometric smdy provides an estimation method therapeutic dmgs possessing antifungal. 

Safin, D.K. and Chmutova, G.A. (1985) Solvation effects in complexation reactions, n. Sol-vatochromism and the nature of absorption bands in the electronic spectra of charge-transfer complexes between iodine and Group VIA element-containing organic compounds. Zh. Ob-shch. Khim., 55, 2564-2572. 

Devillanova, RA. and Verani, G. (1979) Charge transfer complexes between iodine and the thioamido entity contained in some pentaatomic rings. J. Heterocycl. Chem., 16, 945-948. 

A typical cell is constructed by placing in contact a lithium anode and an electronically conducting charge-transfer complex of iodine and poIy-2-vinylpyridine (P2VP) containing an excess of iodine. A thin layer of lithium iodide is inunediately formed, which becomes the electrolyte of the cell and prevents any further direct reaction between the active cell components. 

Further characterization of the ozone—mesitylphenylethylene complex produced at —150 °C was done by NMR and visible spectral studies. The low temperature NMR spectra of the starting olefin, the red complex (ozonized olefin at —150°C) and the dilute reaction mixture at —135°C containing the epoxide of 1-mesityl-1-phenylethylene are described in Table III. The —150 °C solutions of the olefin and the complex contain the same bands, the only difference being that the peaks were shifted slightly upfield in the formation of the complex. Such is typical of tt complexes with very little charge transfer, such as iodine and tetracyano-ethylene complexes of various aromatic molecules (5, 6). When the temperature of the ozonized reaction mixture was allowed to rise above about —145 °C, the NMR spectrum changed, giving rise to the characteristic peaks of the epoxide of 1-mesityl-l-phenylethylene. 

In the above radical-cation salts, the crystal contains partially oxidized donors, while the electroneutrality is achieved by the presence of closed shell anions. The structural requirements necessary for electrical conductivity in solid salts can also be met upon mixing of donors and acceptors in the resulting charge-transfer (CT) complexes both the donor and acceptor exist in a partially oxidized and reduced state, respectively. Famous examples are the conducting CT complexes formed upon mixing of perylene (112) [323. 324] and iodine or of tetrathiafulvalene (TTF, 119) as donor and 7,7,8,8-tetracyanoquinodimethane (TCNQ, 120) as acceptor [325-327] the crucial structural finding for the... 

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