Cerium(IV) Trihydroxide Hydroperoxide1

Ce(OH)3O2H

[93131-81-8]  · CeH4O5  · Cerium(IV) Trihydroxide Hydroperoxide  · (MW 224.12)

(mild oxidizing reagent for a variety of functional groups2,3

Solubility: insol H2O, MeCN, EtOH, DMSO, THF.

Form Supplied in: orange-red solid, readily available.

Preparative Method: by the addition of 30% hydrogen peroxide solution (20 mL) to a solution of CeCl3.7H2O (0.03 mol) in water (100 mol). Upon addition of conc NH4OH (15 mL), precipitation of the reagent occurs, which is then washed with water, acetone, and dried in the air (95%).2

Handling, Storage, and Precautions: stable at high temperatures >180 °C and for months at rt. Cerium is reputed to have low toxicity.

Heterogeneous oxidations with this reagent (CTH) proceed in dry benzene under reflux. The oxidant is separated by filtration. Evaporation of the solvent and chromatography of the residue affords the oxidation product. Several drawbacks observed with CeIV oxidations1a,4 are not encountered with CTH. Change of color from red-orange to pale yellow indicates the deactivation of the reagent, which can be regenerated by two consecutive washings with sodium hydroxide (54-10%) followed by hydrogen peroxide (30%) solutions.

Oxidations.

Allylic, propargylic, and saturated alcohols are not easily oxidized with this reagent, although benzylic alcohols are transformed to their aldehydes (eq 1).

Benzoins are converted to the benzils (eq 2) and hydroquinones to quinones (eq 3) in high yields.

a-Hydroxycarboxylic acids are converted to carbonyl compounds with degradation (eq 4), and thiols are oxidized to disulfides (eq 5) in excellent yields.

Aromatic amines are transformed to azo compounds (eq 6).

A comparison of CTH with Cerium(IV) Ammonium Nitrate (CAN),4,5 Nickel(II) Peroxide (NP),6 and 2,2-bipyridylchromium peroxide (BPCP)7 is shown in Table 1.


1. (a) Ho, T. L. In Organic Syntheses by Oxidation with Metal Compounds; Mijs, W. J.; deJonge, C. R. H. I., Eds.; Plenum: New York, 1986; p 569. (b) Molander, G. A. CRV 1992, 92, 29.
2. Firouzabadi, H.; Iranpoor, N. SC 1984, 14, 875.
3. Firouzabadi, H.; Iranpoor, N.; Hajipoor, G. H.; Kiaeezadeh, F.; Razee, S.; Toofan, J. Iran. J. Sci. Technol. 1987, 11, 247.
4. Ho, T. L. S 1973, 347
5. Trahanovsky, W. S.; Young, L. B.; Brown, G. L. JOC 1967, 32, 3865.
6. Nakagawa, K.; Tsuji, T. CPB 1963, 11, 296.
7. Firouzabadi, H.; Iranpoor, N.; Kiaeezadeh, F.; Toofan, J. T 1986, 42, 719.

H. Firouzabadi

Shiraz University, Iran



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