Lithium telluride

Attempts to synthesise tritellurophosphonic acids or their salts have so far proved unsuccessful, and synthetic routes from primary phosphines analogous to Equation 39 with E = Te give just cyclic polyphosphanes (RP) and lithium telluride with no observed tritellurophosphonate formation.45... 

Tetraphenyltellurophene A solution of 1,4-diiodotetraphenyl-l,3-butadiene (2.0 g, 3.3 mmol), finely powdered lithium telluride (1.5 g, 11 mmol), in 125 mL of 2-ethoxyethyl ether is heated at reflux, under stirring and flushing with N2, for 8 h. The mixture is then poured in 1000 mL of water, the organic phase is separated and submitted to usual workup. After evaporation, the residue is recrystallized from dicloromethane/ethanol, giving the product 1.3 g (82%), m.p. 239°C. 

Not included in the former sections are methodologies involving arene-catalyzed lithiation that are based on deprotonation reactions, carbon-carbon bond cleavage, addition processes as well as the preparation of lithium telluride. 

Lithium telluride (Li2Te) was prepared from elemental tellurium and lithium in the presence of a catalytic amount of naphthalene in THF at room temperature, and then used for the preparation of teUurophenes . 

A range of group 13 derivatives results from the tellurol and [Me3Si)2N]3Al and Cp3 In, the Ga derivative from the lithium telluride and GaCl3. They readily give complexes as does the In(I) derivative96. 

The lithium telluride substitutes TiCl3(THF)3 and (PhCH2)4M react with the tellurol, the [(Me3Si)3SiTe]4M derivatives complexing with isocyanides or dmpe, the latter inducing decomposition to the disilyl telluride and metal telluride97 (equation 48). 

Lithium telluride, prepared from tellurium and lithium triethylborohydride in tetrahydrofuran2, and sodium telluride, obtained from sodium and tellurium in a dipolar, aprotic solvent or from tellurium2,5 and Rongalite in aqueous sodium hydroxide2, reacted with aliphatic2,3,6 and aromatic5 dihalides to produce polymeric organo tellurium compounds. 

By writing Li2Se and Li2Te for lithium selenide and lithium telluride, we do not wish to claim that the exact nature of these molecular formulae is known. 

Benzo[l,2-c 3,4-c 5,6-c"]tritellurophene might have been prepared by dehydrogenation of the product obtained in the reaction between hexakis[bromomethyl]benzene and lithium telluride. Experimental details for the preparation of these compounds were not reported. 

Silastannathianes containing the unit SiSSn can be prepared from the reaction of a mixture of tin halide and silicon halide with hydrogen sulfide in the presence of an amine, and the corresponding selenium and tellurium compounds from a similar reaction using lithium selenide or lithium telluride.14... 

The procedure is based on the reaction of lithium ethynyltellurolates (generated by the successive treatment of acetylenes with n-BuLi and elemental tellurium) with iodochloromethane giving ethynylchloromethyl tellurides. Subsequent reaction with lithium telluride forms lithium(ethynyltelluro) methane tellurolates which cyclize via an intramolecular addition of the tellurolate to the ethynyltelluro moiety. ... 

After some previous unfruitful attempts,43 44 the first synthesis of the tellurophene nucleus was finally accomplished in 1961 by Braye et a/.,43,46 who prepared tetraphenyltellurophene by two alternative procedures, using 1,4-dilithiotetraphenylbutadiene and tellurium tetrachloride (yield 56%) and from 1,4-diiodotetraphenylbutadiene and lithium telluride (82%). 

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