Thallium -carbonate

Thallium carbonate (Tl COj) is used to make artificial diamonds (along with several other thallium compounds). 

Thallium fluoride is prepared by reacting thallium carbonate with hydrofluoric acid. Also, the compound can be made by reacting thaUium metal with fluorine. 

Thallium oxide also can he prepared hy thermal dissociation of thallium hydroxide, TlOH or thallium carbonate, TI2CO3. Thallium oxide dissolves in water forming thallous hydroxide, TlOH. It reacts with carbon dioxide to form thallous carbonate, TI2CO3. 

These expected valueB of bond lengths are in reasonably good agreement with those reported from the microwave investigation 2.70 0.01 A for thallium-carbon and 1.43 0.02 A for carbon-carbon. 

Thallium Orthovanadate, T13V04, is a light brown substance obtained by carefully fusing three molecular proportions of thallium carbonate... 

Thallium Pyrovanadate, T14V20 is precipitated as a light yellow powder by the addition of thallium sulphate to a cold, saturated solution of sodium orthovanadate. It also results on fusing a mixture of vanadium pentoxide and thallium carbonate.14 It melts at 454°15 or 416° C.,16 and is soluble in about 5000 parts of water at 14° C. 

Fused ring 7-lactones may also be formed by cyclizations of l-cycloalkeneacetic acids under equilibrating conditions. Nicolaou obtained evidence for the presence of an unstable -lactone in the phenyl-selenolactonization of 1-cyclohexeneacetic acid, but rearrangement occured readily at room temperature to the more stable 7-lactone (equation 12).32 An example of a one-step conversion of a 2-methyl-1-cyclohexeneacetic acid to a fused butenolide by use of diphenyldiselenide and electrochemical oxidation has been reported.47 Recent studies by Rutledge showed that simultaneous addition of bromine and thallium carbonate to 1-cyclohexeneacetic acid gave the 7-lactone as the exclusive product (compare to Table 2) however, the mechanism of this reaction may differ from other cyclofunctionalizations.21... 

Many investigations have been performed in order to elucidate the structure and bonding in cyclopentadienylthallium(I) compounds. Various bonding situations are found in this class. The parent compound, cyclopentadienyl-thallium (LHIa) is nearly unsoluble in polar solvents. It is rather stable to air and water and sublimable in a vacuum. The microwave spectrum (178) suggests a half-sandwich structure in the gas phase with a thallium to ring centroid distance of 2.41 A (see Fig. 11). The thallium-carbon distances of... 

Figure 11. Thallium carbon atomic ratio from zero adjustable parameter theory vs. observed values...

PtN2S]oHg, Platinate(II), bis(pentasulfido)-, bis(tetrapropylammonium), 20 13 PtNgSisHs, Platinate(IV), tris(pentasulfido)-, diammonium, 21 12, 13 PtN403Tl4Cs, Platinate(II), tetracyano-, thallium carbonate (1 4 1), 21 153,... 

Derivation Interaction of acetic acid and thallium carbonate. 

Photolysis of diethylthallium bromide in cyclohexane is a radical process involving cleavage of the thallium-carbon bond, which yields ethylcyclohexane and dicyclohexyl, as well as other products. Photoelectron transfer from benzyltributylstannanes to 10-methylacridinium ion results in cleavage of the metal-carbon bond, to give the corresponding benzyl radicals, rather than benzyl cations. Photochemical homolysis of Re- and Ru-alkyl bonds in Re(alkyl)-(CO)3(diimine) and Ru(I)(alkyl)(CO)2(diimine) complexes has been studied by Fourier transform ESR. In related manganese complexes, Mn(R)(CO)3(di-imine), elimination of CO is the predominant pathway when R = methyl, but Mn-alkyl homolysis occurs when R = benzyl. 

THALLIUM CARBONATE or THALLIUM(I) CARBONATE (6533-73-9) CHjOj 2Tl Noncombustible solid. Inconq)atible with strong oxidizers, strong... 

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