Peracetic acid Baeyer-Villiger reaction

Baeyer-Villiger reaction of 57 with H3PO5 gives the phenol 59. However, the peracetic acid or trifluoroperacetic acid gives the carboxylic acid 58 (equation 93). Oxidation of V,V-dimethylaniline in aqueous CH3CN at 30 °C affords the V-oxide in 82% yield . 

Ketones react with peracids (RCO3H) to give esters in the Baeyer-Villiger oxidation. The peracid is usually m-chloroperbenzoic acid (mCPBA) peracetic acid and trifluoroperacetic acid are also commonly used. Peracids have an O—OH group attached to the carbonyl C. They are no more acidic than alcohols, because deprotonation of the terminal O does not give a stabilized anion, but they are usually contaminated with some of the corresponding acid. The Baeyer-Villiger reaction is thus usually conducted under mildly acidic conditions. Protonation of the ketone O occms first to make the carbonyl C even more electrophilic than it... 

Scheme 9.176. A representation of the reaction of the ethyl ester of cyclohexanone-2-car-boxylic acid with excess permethanoic acid (peracetic acid, CH3CO3H). The labile epoxide presumed to be produced from the corresponding enol is expected to rearrange to a ketone, which undergoes the Baeyer-Villiger reaction.

The CL monomer is obtained by the traditional Baeyer-Villiger reaction, starting from cyclohexanone as substrate. However, this synthetic route is not environmentally friendly, which has involved the development of two greener routes (1) use of a peroxycarboxylic acid (such as 3-chloroperbenzoic acid or peracetic acid) in dichloromethane at 40 ° C, and (2) use of hydrogen peroxide as oxidizer and zeolite/tin catalysis.The second process is considered the greenest because the main by-product is exclusively water and the tin-impregnated zeolite is an environmentally friendly catalyst. Nowadays, CL is produced by several manufacturers like BASF (USA), Perstorp (UK), and Daicel Chemical Industries Ltd. (Japan). 

The Baeyer-Villiger oxidation of acyl-substituted cyclobutanones 1 is reported to be very slow with ordinary peracids such as 3-chloroperoxybenzoic acid24- 31 37 38 and peracetic acid.24,36 Generally, reaction times of several weeks are needed to obtain acceptable yields of acyloxycy-... 

The Lewis acidity of Zr in amorphous zirconium phosphate has been exploited for the Baeyer-Villiger oxidation of ketones with H202 as the oxidant (209). Excellent results are obtained for reaction in acetic acid. However, it is difficult to distinguish between the contributions of in situ formed peracetic acid and an inorganic Zr peracid. In the reaction in acetonitrile, the yields of oxidized products are modest ... 

Percarboxylic acids have been used widely in Baeyer-Villiger oxidation. Peracetic acid is one of the most commonly used peracids distilled peracetic acid is employed commercially by Solvay Interox for the production of e-caprolactone.246 The use of distilled peracetic acid is essential, as it contains no strong protic acids which can catalyse polymerization of the resulting lactone and cause other side reactions. Figure 3.53 illustrates the use of pre-formed peracetic acid for the Baeyer-Villiger oxidation of ketones.247,248... 

We have found it useful to prepare authentic samples of the various diperoxides encountered by using a variation of the Baeyer-Villiger oxidation conditions. Oxidation of ketones at low temperatures using peracetic acid has been reported (23) to give diperoxides instead of the esters produced under Baeyer-Villiger conditions. Authentic samples of 10 and 11, can be prepared, respectively, by the peracetic oxidation of acetone and methyl ethyl ketone jointly or methyl ethyl ketone alone. We are studying the mechanism of this interesting oxidation reaction. 

Carbonyl Compounds Peracetic acid attacks a-carbonyl groups in lignin model compounds [75,78,82-86]. The reaction occurs readily according to a Baeyer-Villiger oxidation. Nimz and Schwind [78] obtained significant yields of hydroquinone... 

Phenols with p-carbonyl Substituents Acetovanillone (VI) reacted more rapidly than phenols that had no p-carbonyl substituent. The maximum rate of reaction occurred near pH 8 [88]. Strumila and Rapson [82] obtained Baeyer-Villiger oxidation products, methoxyhydroquinone and its monoacetate, from neutral peracetic acid treatment of acetovanillone. From vanillin they obtained only vanillic acid. 

The Baeyer-Villiger oxidation of delfone (2-pentylcyclopentan-l-one) to 5-decalactone (6-pentyloxan-2-one) finds applications in flavour and fragrance markets. The reaction is known to proceed with retention of configuration with peracetic acid, while producing acetic acid as a byproduct. An environmentally friendly alternative has been reported using Sn-Beta catalyst. The 8-decalactone was obtained in 86% yield when the... 

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