Ganem oxidation

C5H5N-O or 2-Me-C5H5N—0 / NaHC03 / solvent / heat Ganem oxidation... 

A novel synthetic approach was developed by R.E. Taylor et al. for the preparation of the triene portion of the biologically active polyketide apoptolidin. The allylic chloride substrate was prepared from an allylic alcohol via a thionyl chloride mediated rearrangement. Next, the allylic chloride was subjected to the Ganem oxidation by treating it with five equivalents of trimethylamine A/-oxide (TMANO) in DMSO at room temperature to obtain the desired a,p-unsaturated aldehyde. Interestingly, the original Kornblum oxidation conditions were not well suited for this system because of the required high reaction temperature. 

This reaction was first reported by Corey and co-workers in 1968. It is an efficient synthesis of o ,j8-unsaturated esters by treatment of o, j0-unsaturated aldehydes (or allyl aicohois) with manganese dioxide and potassium cyanide in a proper alcohol. This reaction is thus known as the Corey-Gilman-Ganem oxidation in general or simply the Corey-Ganem oxidatin. ... 

It is believed that this reaction involves the formation of cyanohydrins, which are then converted into the corresponding acyl cyanides the acyl cyanides are subsequently transformed to either acids or esters in the presence of appropriate solvents, such as acetic acid or methanol.A tentative illustration of the mechanism for the Corey-Gilman-Ganem oxidation is thus given here. 

Other references related to the Corey-Gilman-Ganem oxidation are cited in the literature. ... 

Horner and Jurgens39 reported that benzoyl peroxides 21 in the presence of sulphides decompose to give sulphoxides and a-acyloxysulphides 22 (equation 8). The latter compounds are undoubtedly formed as a result of the Pummerer reaction. The oxidation reaction leading to sulphoxides has been shown to be an ionic process40. However, till now it has not found wider synthetic applications. Ganem and coworkers41 showed that 2-hydroperoxyhexafluoro-2-propanol 23 formed in situ from hexafluoroacetone and... 

As peracids react very sluggishly with alcohols, it was apparent that the presence of a nitroxide was playing an important role in the oxidation of the alcohol into a ketone. This seminal serendipitous observation led to the development of the first description of the oxidation of alcohols mediated by catalytic 2,2,6,6-tetramethylpiperidine-l-oxyl (TEMPO) (55), published almost simultaneously by Celia et al and Ganem.3 These authors presented two papers with remarkably similar contents, in which alcohols were oxidized by treatment with MCPBA in CH2CI2 at room temperature in the presence of a catalytic amount of TEMPO (55). In both papers, a plausible mechanism is presented, whereby m-chloroperbenzoic acid oxidizes TEMPO (55) to an oxoammonium salt 56. This oxoammonium salt 56, as detailed in Ganem s paper, can react with the alcohol producing an intermediate 57, which can deliver a carbonyl compound by a Cope-like elimination. 

Corey EJ, Gihnan NW, Ganem BE (1968) New Methods for the Oxidation of Aldehydes to Carboxylic Acids and Esters. J Am Chem Soc 90 5616... 

Ganem, B., Boeckman, R. K., Jr. Silver-assisted dimethyl sulfoxide oxidations. Improved synthesis of aldehydes and ketones. Tetrahedron Lett. 1974, 917-920. 

Godfrey, A. G., Ganem, B. Ready oxidation of halides to aldehydes using trimethylamlne N-oxIde In dimethyl sulfoxide. Tetrahedron Lett. 1990, 31, 4825-4826. 

According to Ganem (11), N-oxyl radical can oxidize aliphatic alcohols to ketones. A similar reaction might be presumed between N-oxyl radical and IRGANOX 1010 (assumed also by Allen (12)), giving a resonance-stabilized quinone radical and a hydroxyl amine (Equation 1). This quinone is photoactive, and sensitizes the photooxidation of the polymer via hydrogen abstraction or hydroperoxide formation. 

Ganem has also reported oxidation of secondary alcohols to ketones in about... 

Oxidation of 3 by the method of Ganem and Boeckman (5, 264) leads to -pliciiylseleno ketones (5). A somewhat different route to these ketones has also been reported by Japanese chemists (equation I). These ketones can be alkylated... 

Reaction with an arene oxide-oxepin (5, 489-490 6, 435-436). Holbert and Ganem have synthesized the naturally occurring senepoxide as the DL-racemate... 

Ganem JJ, Battistig G, Rigo S, Tiimaille I (1993) A study of the initial stages of the oxidation of silicon using Oi8 and RTP. Appl Surf Sci 65(66) 647-653... 

A soln. of 85%-m-chloroperoxybenzoic acid in methylene diloride added to a stirred ice-cooled soln. of 5-norbornen-2-ol in the same solvent, after 2 hrs. treated with a soln. of 2,2,6,6-tetramethylpiperidine hydrochloride in methylene chloride followed by additional m-chloroperoxybenzoic acid soln., and the product isolated after 1.5 hrs. exo-5,6-epoxy-2-norbornanone. Y 86%. J. A. Celia, J. A. Celia, J. A. Kelley, and E. F. Kenehan, J. Org. Chem. 40, 1860 (1975) oxidation of alcohols with N-oxide radicals cf. B. Ganem, ibid. 40, 1998 ketones from sec. alcohols with m-chloroperoxybenzoic acid/HCl cf. J. A. Celia, J. P. McGrath, and S. L. Regen, Tetrah. Let. 1975, 4115 review of N-oxide radicals s. H. G. Aurich and W. Weiss, Topics Curr. Chem. 59, 65 (1975). 

Ganem B, Holbert G W 1977 Arene oxides in biosynthesis. On the origin of crotepoxide, senepox-ide, and pipoxide. Bioorg Chem 6 393-396... 

Ganem B, Holbert G W, Weiss L B, Ishizumi K 1978 A new approach to substituted arene oxides. Tbtal synthesis of senepoxide and seneol. J Am Chem Soc 100 6483-6491... 

Schulte G R, Ganem B, Chantrapromma K, Kodpinid M, Sudsuansri K 1982 The structure of ferrudiol. A highly oxidized constituent of Uvaria ferruginea. Tetrahedron Lett 23 289-292... 

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