Sodium telluride synthesis

A comprehensive work on the electrodeposition chemistry and characterization of anodically synthesized CdTe thin films has been presented by Ham et al. [98]. In this work, along with the electrolytic anodic synthesis of CdTe by using Cd anodes in alkaline solutions of sodium telluride, an electroless route of anodizing a Cd electrode held at open circuit in the same solution was also introduced. The anodic method was expected to produce CdTe with little contamination from Te on account of the thermodynamic properties of the system the open-circuit potential of Cd anodes in the Te electrolyte lies negative of the Te redox point, so... 

Synthesis of compound A.A solution of 1,3-dibromopropane (10.1 g, 0.05 mol) in benzene (100 mL) was added to a solution of sodium telluride (NajTe 17.4 g, 0.1 mol) in ethanol (700 mL). After 3 h sodium borohydride (3.8 g, 0.1 mol) was further added to the mixture to produce sodium propane-1,3-ditellurolate, and then to the mixture was added a solution of the dibromopropane (10.1 g, 0.05 mol) in benzene (100 mL). The whole mixtnre was stirred at room temperature for 2 h. After usual work-up, the crude products were purified by silica gel column chromatography (eluent n-hexane/benzene) to afford compound A, which was further purified by preparative liquid chromatography. 

Whereas no other methods of synthesis of 21 and its derivatives are currently known, the nucleophilic addition of telluride anion to 1,5-diorganylpentadi-1,4-ynes may be considered a promising approach, based on the finding that sodium telluride reacts smoothly with monosubstituted alkynes, giving rise to divinyltellurides (89MI1). 

An unusual synthesis of a pyrrolo[2,3- ]pyrimidine without a functional group is based on the reaction of benzonitrile with A-methyl-2-pyrrolidone. These two compounds, when heated in the presence of sodium telluride, give low yields of 2,4-diphenyl-7-methylpyrrolo[2,3- ]pyrimidine <93JOC24l>. The yields could not be improved, thereby limiting the usefulness of the method. 

A synthesis which is more convenient for the small-scale preparation of tellurophene employs sodium telluride, formed by the reduction of tellurium with sodium formalde-hydesulfoxylate in aqueous sodium hydroxide, and 1,4-bis[trimethylsilyl]-l, 3-butadiyne2... 

In an extension of their synthesis of 2-nitrothiophenes, Cagniant and co-workers have prepared 2-nitroselenophenes and -tellurophenes by similar procedures.32,33 Thus, the / -chloro-a,/ -unsaturated aldehyde 38 (R = Ph R = H) reacts with bromonitromethane and sodium selenide to form the 2-nitroselenophene 39. Similarly, with sodium telluride and bromonitromethane, chlorovinylaldehydes yield 2-nitrotellurophenes (40). 

Nucleophilic addition of sodium telluride to 1,3-diynes serves as a general method for the synthesis of 2- and 2,5-disubstituted tellurophenes (Equation 18) <1966AG940, 1968BRP1107698, 1972ADC777, 1972J(P1)199,... 

Naphthaceno[5,6-c,c ll,12-c, (/ ]bis[l,2]ditellurole, the tellurium analogue of (14), was prepared by the reaction of the corresponding tetrachlorotetracene with a new sodium telluride reagent formed directly from the elements in a 1 1 atomic ratio <820M739>. The synthesis of derivatives with functional groups has been described <85GEP(0)3510090,88MIP664154>. 

Cagniant et al.sl have extended to tellurophenes a method of synthesis, recently developed for thiophenes and selenophenes,33 34 based on the condensation of a /J-halovinyl aldehyde with sodium telluride and a halogeno derivative of general formula X—CH2—R [Eq. (2)]. Some mono and polycyclic derivatives of tellurophene have been prepared using the above procedure. 

The authors also synthesized tellurol esters by successive acylation and alkylation of sodium telluride (Na2Te) via tellurocarboxylates [115]. Suzuki, Tani and co-workers succeeded in the synthesis of tellurol esters by a similar method using sodium hydrogen telluride (NaTeH) (Eq. 60) [116]. 

Tellurophens.—A detailed description of the synthesis of tellurophen (701) from sodium telluride and butadiyne has been published. Its chemical properties are similar to those of thiophen and selenophen. It can be... 

Another application of the above hydrotelluration protocol involves the synthesis of unsymmetrical divinyl tellurides by the addition of sodium vinylic tellurolates, generated... 

Synthesis of internal acetylenes Into a CHCI3 solution (5 mL) of vinylic telluride (2 mmol) was added an aqueous sodium hypochlorite solution (5-8 equiv) at 25°C, and the mixture was stirred for 30 min. The products were extracted with CHCI3, and the extract was dried over MgS04, concentrated and heated gradually in a Kiigelrohr distillation apparatus up to 250°C in vacuo, giving rise to the corresponding internal acetylenes. 

In the area of 2, 3 -didehydro-2, 3 -dideoxynucleosides, a new route to compounds of this type in the pyrimidine series is outlined in Scheme 4. The thioglycoside 54 was produced directly from deoxyribose and thiophenol in acidic conditions, and the condensations to form the nucleoside derivatives were P-selective by about 2 l/ A full account has been given of the formation of 2, 3 -didehydro-2, 3 -dideoxy systems from 2, 3 -dimesylates, protected at 0-5, by treatment with telluride anion (see Vol. 27, p. 247)7 Treatment of the furanoid glycal 55, made by cyclization of an acetylenic alcohol (Chapter 13), with silylated thymine in the presence of iodine, followed by sodium methoxide, provides a new route to d4T (56)7 A new synthesis of d4T (56) from 5-methyluridine has also been described, as has a route to d4T labelled with at C-1, which starts from [l- C]-ribose and proceeds via [r- C]-5-methyluridine, convertible in very high yield to [l - C]-d4T. ... 

Synthesis of CdTe Nanoparticles CdTe nanoparticles are synthesized by first synthesizing bis-(aminoethyl)telluride by reducing the Tellurium powder using sodium borohydrates in presence of THF under the contuous flow of Ar gas at 60-70 C. Disodium telluride is then converted into bis(aminoethyl)telluride as shown in the scheme below in Fig. 16(a) ... 

Conditions have been worked out for the synthesis of methyl polyfluoroalkyl sulphides and 2-bromo-l,l-difluoroethyI phenyl sulphide by halogen-substitution reactions involving sodium thiolates. / -Nitrothiophenol reacts with 1,2-dichlorohexafluorocyclopentene to give the l,2-bis(p-nitrophenylthio)-analogue. Aryl alkyl tellurides PhTeR and bis(phenyltelluro)methane PhTeCHgTePh can be obtained from PhTeLi and an alkyl halide, or di-iodomethane, respectively. 

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