Cerium Ammonium Nitrate, CAN
Cerium (IV) ammonium nitrate ((NH4)2Ce(NO3)6) is a one-electron oxidizing agent that is used for oxidative addition reactions of electrophilic radicals to alkenes, enabling intermolecular and intramolecular carbon-carbon and carbon-heteroatom bond formation. CAN also oxidizes secondary alcohols into ketones and benzylic alcohols into aldehydes.
Recent Literature
The combination of TEMPO and CAN can be used for the aerobic oxidation of
benzylic and allylic alcohols into their corresponding carbonyl compounds.
However, steric hindrance has been observed to impede the reaction with some
substituted allylic systems. The present method is superior to others
currently available due to its relatively short reaction times and excellent
yields.
S. S. Kim, H. C. Jung, Synthesis,
2003, 2135-2137.
Oxidative ring expansion of methylenecyclopropanes with CAN under oxygen
atmosphere was investigated. A facile conversion affording
2,2-diarylcyclobutanones occurred in good yields.
V. Nair, T. D. Suja, K. Mohanan,
Synthesis, 2006, 2531-2534.
A mild oxidation of selected anions (N3-, SCN-, I-, and Br-) by ceric ammonium
nitrate (CAN) in the presence of substituted cyclopropyl alcohols provides β-functionalized
ketones in short reaction times. This method provides an alternative
pathway to important starting materials and intermediates in organic synthesis.
J. Jiao, L. X. Nguyen, D. R. Patterson, R. A. Flowers II, Org. Lett., 2007,
9, 1323-1326.
The reaction of tertiary 1,4- and 1,5-diols with cerium ammonium nitrate at room
temperature gives tetrahydrofuran and tetrahydropyran derivatives in high yield
and stereoselectivity. Various fragrant compounds have been synthesized using
this method.
E. J. Alvarez-Manzaneda, R. Chabouna, E. Alvarez, E. Cabrera, R.
Alvarez-Manzaneda, A. Haidour, J. M. Ramos, Synlett, 2006,
1756-1758.
Singly occupied molecular orbital (SOMO) catalysis allows an enantioselective
organocatalytic α-enolation of aldehydes. A chiral secondary amine catalyst
reacts with aldehydes to form transient enamines that undergo selective
one-electron oxidation to generate SOMO-activated electrophilic radical cations
which are susceptible to attack by ketone-derived enol silanes.
H.-Y. Jang, J.-B. Hong, D. W. C. MacMillan, J. Am. Chem. Soc., 2007,
129, 7004-7005.
The cerium(IV) ammonium nitrate (CAN) mediated reaction of aryl sulfinates
and sodium iodide with alkenes afforded vinyl sulfones in very good yields.
Alkynes underwent a similar reaction to give β-iodovinyl sulfones, which on
treatment with potassium carbonate afforded the corresponding acetylenic
sulfones in high yields.
V. Nair, A. Augustine, T. D. Suja, Synthesis,
2002, 2259-2265.
V. Nair, A. Augustine, T. D. Suja, Synthesis,
2002, 2259-2265.
A facile one-pot CAN-induced cyclodimerization of various styrenes in
acetonitrile or acrylonitrile gave 1-amino-4-aryltetralin derivatives.
V. Nair, R. Rajan, N. P. Rath, Org. Lett., 2002,
4, 1575-1577.
Ceric ammonium nitrate efficiently catalyzes the aza-Michael reaction of amines
with α,β-unsaturated carbonyl compounds in water to produce the corresponding
β-amino carbonyl compounds in very good yields under mild conditions. The
reaction is procedurally simple and offers limited chemoselectivity, as aromatic
amines were found to be unreactive.
R. Varala, N. Sreelatha, S. R. Adapa, Synlett, 2006,
1549-1553.
Ceric ammonium nitrate catalyzes the reaction between aromatic or aliphatic
primary amines and a variety of β-dicarbonyl compounds, including β-ketoesters,
β-ketothioesters and β-diketones to give β-enaminones in good to excellent
yields at room temperature in short reaction times.
V. Sridharan, C. Avendaño, J. Carlos Menéndez, Synlett, 2007,
2133-2142.
