IV Ammonium Sulfate

Form Supplied in orange solid, widely available. 

Cerium(IV) ion is a potent one-electron oxidant. cerium(IV) ammonium nitrate (CAN), is the most widely utilized cerium(rV) oxidizing agent, but cerium(IV) ammonium sulfate (CAS) is a good substitute when complications due to the involvement of nitrate ligands occur, resulting in side products such as nitrate esters.  

The most important application of CAS is in the oxidation of aromatic rings. CAN oxidizes polycyclic aromatic hydrocarbons only in moderate yields (20-60%), and these reactions are often complicated by the formation of nitrate esters. In contrast, CAS generally oxidizes aromatic hydrocarbons to quinones in good yields. For example, naphthalene is oxidized to 1,4-naphthoquinone in excellent yield by CAS in a dilute mixture of H2SO4 andMeCN(eq 1).  

Other polycyclic aromatic hydrocarbons such as phenanthrene, anthracene, and fluoranthene are converted to the corresponding quinones on oxidation with CAS. Whereas 1-methylnaphthalene gives 1-naphthaldehyde under the conditions, 1-phenyl- and 1-bromonaphthalene react to form some 2-substituted naphthoquinones through an interesting rearrangement (eq 2).  

A list of General Abbreviations appears on the iront Endpapers 

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Ceric sulfate, O.liV Ce(IV) to Ce(III). Dissolve 63.26 g of cerium(IV) ammonium sulfate dihydrate in 500 mL of 2N sulfuric acid. Dilute the solution to 1 L and standardize against the... 

Ciprofloxacin was determined in tablets and intravenous infusion solutions by an oxidative spectrophotometric method [15]. A yellow-orange complex was obtained upon reaction of ciprofloxacin with 5% ammonium sulfamate, 5 N H2S04, and 0.1 M cerium(IV) ammonium sulfate. The complex was extracted into CHC13, dried with anhydrous Na2S04, and measured at 345 nm within up to 4 h. Beer s law was obeyed over the range of 12-120 pg/mL, and the molar absorptivity was found to be 5090. 

Preparation In the early work with Ce(IV), standard solutions were prepared from relatively crude preparations of Ce(rV) oxide, Ce(TV) sulfate, or Ce(IV) ammonium sulfate. Contamination from other lanthanides and phosphate led to the gradual precipitation of lanthanide phosphates from a sulfuric add solution. 

Cerium(IV) ammonium sulfate Ceric ammonium sulfate [7637-03-8] hydrate [10378-47-9] anhydrous Commercially available... 

Fig. 3. Coordination sphere of cerium(IV) ammonium sulfate (Shan and Huang, 1998).

Polycyclic ketones undergo Baeyer-VilUger oxidation with ammonium hexanitratocerate(IV) or cerium(IV) ammonium sulfate to afford lactones (Soucy et al., 1972 Mehta et al., 1976). The Baeyer-Villiger oxidation of adamantanone to the corresponding lactone is shown above in scheme 14. Camphorquinone is oxidized to a complex mixture of oxidation products (Danieli and Palmisano, 1976). Simple aliphatic ketones are not oxidized by cerium(IV) in the absence of a catalyst. In presence of ruthenium(III) chloride, cerium(IV) sulfate oxidizes 2-butanonone to acetic acid and formic acid, and 3-pentanone to a mixture of propionic acid, acetic acid and formic acid (Singh et al., 1980). 

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