Chemicals >> Oxidizing Agents > Peroxy acids

3-Chloroperoxybenzoic acid, MCPBA, meta-Chloroperbenzoic acid

MCPBA is a strong oxidizing agent, which is comparable with other peracids. Advantages of 3-chloroperbenzoic acid is its handling, because it is present as powder, which can be kept in the refrigerator. Nevertheless, material of purity >75% is rarely available commercially, since the pure compound is not particularly stable. Therefore the transport in airplanes with a content of > 72% is forbidden. Main pollution is 3-chlorobenzoic acid (10%) as well as for safety reasons water.

MCPBA is versatile applicable as peracid for use in laboratories.

Main areas are the oxidation of

aldehydes and ketones to esters (Bayer-Villiger-Oxidation)
olefines to epoxides
sulfides to sulfoxides and sulfones
amines to nitroalkanes, nitroxides or N-oxides

However, for reasons of the atomic economy, the use of MCPBA in production should be avoided. The research concentrates within this area rather on the use of hydrogen peroxide in connection with suitable catalysts or in situ generated, simpler peracids, such as peracetic acid or on potassium peroxymonosulfate (Oxone). In many reactions MCPBA with an outstanding reactivity is however more selective than hydrogen peroxide and other peracids.

Name Reactions

Prilezhaev Reaction

Rubottom Oxidation

Recent Literature

Use of a solvent with greater density than the fluorous phase is an alternative to the U-tube method in phase-vanishing reactions in cases where both reactants are less dense than the fluorous phase.
N. K. Jana, J. G. Verkade, Org. Lett., 2003, 5, 3787-3790.

N. K. Jana, J. G. Verkade, Org. Lett., 2003, 5, 3787-3790.

The results of a highly diastereoselective epoxidation of allylic diols derived from Baylis-Hillman adducts are reported.
R. S. Porto, M. L. A. A. Vasconcellos, E. Ventura, F. Coelho, Synthesis, 2005, 2297-2306.

Several amides were obtained in high yields by an efficient method from the corresponding imines which are readily prepared from aldehydes. This procedure involves the oxidation of aldimines with m-CPBA and BF₃·OEt₂. In this reaction, the product is strongly influenced by the electron releasing capacity of the aromatic substituent (Ar).
G. An, M. Kim, J. Y. Kim, H. Rhee, Tetrahedron Lett., 2003, 44, 2183-2186.

An efficient oxidation of cyclic acetals provided hydroxy alkyl esters in good yields in the presence of MCPBA.
J. Y. Kim, H. Rhee, M. Kim, J. Korean Chem. Soc., 2002, 46, 479-483.

Various α-tosyloxyketones were efficiently prepared in high yields from the reaction of ketones with m-chloroperbenzoic acid and p-toluenesulfonic acid in the presence of a catalytic amount of iodobenzene.
Y. Yamamoto, H. Togo, Synlett, 2006, 798-800.

Reaction of methyl sulfinates with lithium amides followed oxidation of the resulting sulfinamides provides primary, secondary, and tertiary alkane-, arene- and heteroarenesulfonamides in high yields. This protocol avoids the use of hazardous, unstable, or volatile reagents and does not affect the configurational stability of the amines.
J. L. C. Ruano, A. Parra, F. Yuste, V. M. Mastranzo, Synthesis, 2008, 311-312.

The synthesis of N-cyanosulfilimines can readily be achieved by reaction of the corresponding sulfides with cyanogen amine in the presence of a base and NBS or I₂ as halogenating agents. Oxidation followed by decyanation affords synthetically useful sulfoximines.
O. García Mancheño, O. Bistri, C. Bolm, Org. Lett., 2007, 9, 3809-3811.

A new, regiospecific, sequential one-pot synthesis of symmetrical and unsymmetrical diaryliodonium tetrafluoroborates, which are the most popular salts in metal-catalyzed arylations, is fast and high-yielding and has a large substrate scope. Furthermore, the corresponding diaryliodonium triflates can conveniently be obtained via an in situ anion exchange.
M. Bielawski, D. Aili, B. Olofsson, J. Org. Chem., 2008, 73, 4602-4607.

A direct synthesis of symmetric and unsymmetric electron-rich diaryliodonium salts delivers diaryliodonium tosylates in high yields using MCPBA and toluenesulfonic acid. An in situ anion exchange has also been developed, giving access to the corresponding triflate salts.
M. Zhu, N. Jalalian, B. Olofsson, Synlett, 2008, 592-596.