Through Replacement of Hydrogen Atoms

2-Nitrophenoxatellurin To a mixture of 330 ml of nitric acid (rf = 1.50) and 500 ml of glacial acetic acid at 20° are gradually added 50 g (0.17 mol) of phenoxatellurin. The mixture is heated on a boiling water bath for 

25 h until all of the phenoxatellurin 10,10-dinitrate has dissolved and the solution is then poured into a large volume of water containing ice. The precipitate is collected and shaken with a solution of 60 g of potassium disulfite in 200 ml of water. The resultant gummy mass is separated, extracted with chloroform, the extract is dried, and the solvent evaporated. The residue is recrystallized from ethanol/acetone yield  

4-Nitrophenoxatellurin (m.p. 104°) was isolated from the acetone mother liquor from the recrystallization of crude 2-nitrophenoxatellurin  

8-Dinitrophenoxatelliiriii 25 ml of nitric acid (f/ = 1.50) are cooled in an ice/salt bath, 4.3 g (14.5 mmol) of powdered phenoxatellurin are added gradually, and the mixture is heated on a water bath for 0.5 h. The solution is then cooled, water is added, the precipitated white solid is collected, and recrystallized twice from boiling nitric add (d= 1.42). The 2,8-dinitrophenoxatellurin 10,10-dinitrate is reduced by shaking with aqueous potassium disulfite solution and the product is recrystallized from acetone yield 2.9 g (52%) m.p. 228°. 

8-DinitrophenoxatcIlurin 0.4 g (1.2 mmol) of finely powdered 4-nitrophenoxatellurin are added to 5 ml of cold nitric acid (d = 1.50), the mixture is boiled for 2 h, water is then added until the solution becomes turbid, and the product is allowed to crystallize. The white solid is collected, shaken with aqueous potassium disulfite solution, and the product is recrystallized from benzene yield 0.27 g (60%) m.p. 198°. The mother liquor contained small amounts of another dinitrophenoxatellurin. 

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