Tellurium tetrachloride with amines

Tellurium nitride was first obtained by the reaction of TeBt4 with liquid ammonia more than 100 years ago. The empirical formula TeN was assigned to this yellow, highly insoluble and explosive substance. However, subsequent analytical data indicated the composition is Tc3N4 which, in contrast to 5.6a and 5.6b, would involve tetravalent tellurium. This conclusion is supported by the recent preparation and structural determination of Te6N8(TeCl4)4 from tellurium tetrachloride and tris(trimethylsilyl)amine (Eq. 5.5). The TceNs molecule (5.12), which is a dimer of Tc3N4, forms a rhombic dodecahedron in which the... 

The same method was employed for the synthesis of benzo[<2]phenotellurazine 42 and proven to be more efficient. The heterocycle 42 was obtained in 55% yield (89H1007). A possible explanation for the higher yield of 42 is that the transmetallation reaction in this particular case dominates the side formation of nonreactive complex of the amine with tellurium tetrachloride. There is no need for an additional step of the isomerization of the formed aryltellurim trichloride. 

In a related procedure, tellurium tetrachloride is treated with lithium amides giving tellurium(II) amides via the successive reduction and amination of TeCl4. 

Tellurium tetrachloride in combination with a strong amine base effected the mild dehydrosulfurization of thioamides to nitriles. Treatment of the thioamides (60) with tellurium tetrachloride and triethylamine in chloroform at room temperature formed nitriles (61) in excellent yield. Using selenium tetrachloride, a similar reaction also occurred in a little lower yield and accompanied by the formation of the 1,2,4-thiadiazole (63). In a plausible mechanism, some of the 1 1 adduct (61) undergoes a further addition reaction with another thioamide molecule prior to the degradation reaction to nitrile, leading to the formation of the 1,2,4-... 

Phenotellurazines (186) are synthesized by heating the jV-phenyl-A-(2-trichlorotellurodiphenyl)-amines (184) with tellurium tetrachloride, followed by reductive dechlorination of the intermediate... 

Tellurium dioxide complexes with thiourea, 305 Tellurium dithiocyanate complexes, 303 Tellurium hexafluoride complexes, 303 with amines, 304 Tellurium sulfate complexes, 303 Tellurium tetrabromide complexes, 302 Tellurium tetrachloride complexes with acetamide, 304 with amines, 304 with pyridine N-oxide, 304 Tellurium tetrafluoride complexes with amines, 304 with dioxane, 304 Tellurotungstates, 1042 Tempera ture-jump studies molybdenum(VI) complexes, 1259 Terbium complexes p diketones, 1081... 

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