Oxidation of aromatic bis-amides by thallium (III) trifluoroacetate

Aromatic 1,2-bisamides undergo thallium (III) promoted oxidative intramolecular cyclization to generate new 5-membered heterocyclic rings. Formation of $\text{para}$-quinone was shown to be a minor pathway in one case.     

Oxidative coupling of indoles using thallium(III) trifluoroacetate

The oxidative coupling of polysubstituted electron-rich indoles mediated by thallium trifluoroacetate was found to be a facile, clean, and high yielding reaction. Indolic coupling sites were determined by the nature of the substituents present, with dimerisation at the indole 2-position being the dominant outcome. Indoles bearing two potential reaction sites with similar reactivity were additionally found to undergo heterocoupling.     

Synthesis and characterization of four new thallium(I) tetrazole supramolecular compounds with various secondary interactions; new precursors for thallium(III) oxide nano-particles

Four new thallium(I) coordination polymers, [TlBt](n) (1) (Hbt = 5-phenyltetrazole), [TlBbt] (2) (Hbbt = 5-(4-bromobenzyl)tetrazole), [Tl(2)Bdt](n) (3) (H(2)bdt = 5,5'-benzene-1,4-diylbistetrazole), [Tl(2)Pht·H(2)O](n) and [TlBet] (4), (Hbet = 5-(benzyl)tetrazole) have been synthesized and characterized. The single-crystal X-ray data shows that, in compounds 1-3, the coordination sphere of the Tl(I) ion is the same and it is surrounded with six tetrazolate rings. In compound 4, one thallium atom has three interactions with tetrazolate groups and close Tl(I)···π (aromatic) contacts with the phenyl ring. Furthermore, in all cases the single-crystal X-ray data show the same stereo-chemical activity of the valence shell electron lone pair of Tl(I). There is a strong Tl(I)···Tl(I) interaction in one dimension in compounds 1 and 3. All these four compounds have been used as new precursors for the preparation of thallium(III) oxide nano-particles through a simple calcination method. Thallium(III) oxide was characterized by powder XRD diffraction and the morphology of nano particles characterized by scanning electron microscope (SEM).     

Influence of thallium(I) and thallium(III) on parameters of oscillating chemical reaction in a bromate-cerium(III,IV)-malonic acid-sulfuric acid system

The influence of thallium(I) and thallium(III) on the parameters of the Belousov-Zhabotinskii oscillating chemical reaction in the bromate-cerium(III, IV)-malonic acid-sulfuric acid system was studied. As a result of the addition of thallium(I) and thallium(III), the oscillation parameters change in the same way, which cannot be explained by the complexation of these ions with the bromide only. It was found that during the oscillating reaction, thallium(I) can be oxidized by bromine-containing compounds and thallium(III) reduced by the transformation products of malonic and bromomalonic acids. A scheme of action of a thallium(III)/thallium(I) two-electron redox pair in the oscillating chemical reaction studied has been proposed.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 23, No. 1, pp. 106–111, January–February, 1987.     

A metal-free approach to the synthesis of indoline derivatives by a phenyliodine(III) bis(trifluoroacetate)-mediated amidohydroxylation reaction

A novel approach to the synthesis of indoline derivatives is presented. The key cyclization step features the phenyliodine(III) bis(trifluoroacetate)- (PIFA-) mediated formation of a N-acylnitrenium ion and its succeeding intramolecular trapping by the olefin fragment. In addition, difunctionalization of the alkene moiety is achieved since the in situ generation of an additional hydroxy group at the terminal position of the original double bond accompanies the intramolecular C-N bond formation.