Tellurium-Nitrogen Compounds

Submitted by TRISTRAM CHIVERS, NICOLE SANDBLOM, and GABRIELE SCHATTE  

The first structural characterization of a tellurium diimide RNTe(p-N Bu)2TeNR (R = PPh2NSiMe3) was reported in 1994. Subsequently, the synthesis of the symmetric derivative, R = Bu, was achieved by the reaction of Li[HN Bu] with TeClq in a 4 1 molar ratio in toluene. Several LiCl-containing byproducts are also obtained in this solvent. In THF, however, the tellurium diimide, BuN-Te(p-N Bu)2TeN Bu, is obtained in 90% yield and is readily purified. Unlike sulfur or selenium diimides, the tellurium diimides are dimeric and form either cis or 

Department of Chemistry, University of Calgary, Calgary, Alberta, Canada, T2N 1N4. fDepartment of Chemistry, University of Toledo, Toledo OH 43606. 

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Molecular structure and thermochemistry are interrelated here for species chosen from contributions to the earlier Volume 3 of this book series. Discussion includes halogenated species gaseous nonmetal dioxides X-Y bond-containing species (X,Y = C, N, O) small carbon molecules arenols and substituted arenes steroids aromatic carbocycles difluoramines and nitro compounds selenium- and tellurium-nitrogen compounds. 

Tellurium imides comprise another class of tellurium-nitrogen compounds of recent interest.Diorgan-otellurium imides RRTeNR" can formally be considered to contain a Te=N double bond, but the Te-N distance generally falls between the single and double bond lengths. 

T. Chivers (2005) A Guide to Chalcogen-Nitrogen Chemistry, World Scientific Publishing, Singapore - A detailed text that covers sulfur, selenium and tellurium-nitrogen compounds. 

Intramolecular chalcogen interactions may also stabilize reactive functional groups enabling the isolation of otherwise unstable species or their use as transient intermediates, especially in the case of selenium and tellurium. For example, tellurium(II) compounds of the type ArTeCl are unstable with respect to disproportionation in the absence of such interactions. The diazene derivative 15.23 is stabilized by a Te N interaction. Presumably, intramolecular coordination hinders the disproportionation process. Other derivatives of the type RTeX that are stabilized by a Te N interaction include 8-(dimethylamino)-l-(naphthyl)tellurium bromide, 2-(bromotelluro)-A-(p-tolyl)benzylamine, and 2-[(dimethylammo)methyl]phenyltellunum iodide. Intramolecular donation from a nitrogen donor can also be used to stabilize the Se-I functionality in related compounds." ... 

Volume 79 of Advances in Heterocyclic Chemistry commences with an overview of Tellurium-Nitrogen-Containing Heterocycles by I. D. Sadekov and V. I. Minkin of Rostov State University, Russia, andrepresents an update of the review published by the same authors in Volume 58 of Advances, eight years ago. The field has expanded markedly in the recent past, and the compounds show promise in an increasing number of applications, particularly in the material science field. 

Tellurium Halides. Tellurium forms the dihalides TeCl and TeBi, but not Tel2. However, it forms tetrahalides with all four halogens. Tellurium decafluoride [53214-07-6] and hexafluoride can also be prepared. No monohalide, Te2X2, is believed to exist. Tellurium does not form well-defined oxyhalides as do sulfur and selenium. The tellurium halides show varying tendencies to form complexes and addition compounds with nitrogen compounds such as ammonia, pyridine, simple and substituted thioureas and anilines, and ethylenediamine, as well as sulfur trioxide and the chlorides of other elements. 

Polonium Inorganic Chemistry Selenium Inorganic Chemistry Sulfur Inorganic Chemistry Sulfur-Nitrogen Compounds Tellurium Organotellurium Chemistry. ... 

Compound classes, not previously described (eg. 5- and 6-membered heteroarenes) Compound classes, for which, in the meantime, significant improvements and progresses have been made, for example carbonic acid derivatives, carboxylic acids and carboxylic acid derivatives, aldehydes, carbonyl derivatives, halogen compounds, peroxides, sulfur, selenium, tellurium, nitrogen and phosphorus compounds. 

Selenolates such as Na2Se, NaSeH, PhSeNa, etc., and tellurolates such as NapTe, NaTeH, PhTeNa, etc., are excellent nucleophiles and can reduce a variety of functional groups by nucleophilic attack or single electron-transfer. On treatment with alkali metal selenolates (or amine salts of HpSe and PhSeH), reduction or reductive selenation of ketones and aldehydes, C=C reduction of a,/l-unsaturated compounds, and reduction of nitrogen compounds such as nitro compounds occur successfully [118, 176]. Compared with these selenolate anions, the corresponding tellurium compounds are highly reactive not only toward the same substrates but also toward halo compounds such as a-bromo ketones and vic-dibromoalkanes [46, 52, 177]. 

The most sensitive analytical line for tellurium is at 214.281 nm with a characteristic concentration of Co = 0.18 mg/L in an air/acetylene flame. The charaeteristic mass at this line, using a transversely heated graphite tube atomizer, is mo = 17pg. The analytical line at 214.281 nm, as well as that at 225.902 nm, which is about a factor of four less sensitive, is within the range of strong NO absorption bands, which requires special attention in the case of a matrix that contains nitrogen compounds at high concentration. 

Nitrogen and sodium do not react at any temperature under ordinary circumstances, but are reported to form the nitride or azide under the influence of an electric discharge (14,35). Sodium siHcide, NaSi, has been synthesized from the elements (36,37). When heated together, sodium and phosphoms form sodium phosphide, but in the presence of air with ignition sodium phosphate is formed. Sulfur, selenium, and tellurium form the sulfide, selenide, and teUuride, respectively. In vapor phase, sodium forms haHdes with all halogens (14). At room temperature, chlorine and bromine react rapidly with thin films of sodium (38), whereas fluorine and sodium ignite. Molten sodium ignites in chlorine and bums to sodium chloride (see Sodium COMPOUNDS, SODIUM HALIDES). 

Tellurium(VI)-nitrogen bonds can be generated by the reaction of hexamethyldisilazane with tellurium hexafluoride (Eq. 2.12). The product (Mc3SiNH)TeE5 is a useful precursor for a variety of NTeEs compounds. By contrast, SEe is inert towards Si-N reagents. 

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