Magnesium monoperoxyphthalate hexahydrate

Three peroxyacids are produced commercially for the merchant market peroxyacetic acid as a 40 wt % solution in acetic acid, y -chloroperoxybenzoic acid, and magnesium monoperoxyphthalate hexahydrate. Other peroxyacids are produced for captive use, eg, peroxyformic acid generated in situ as an epoxidizing agent. 

Dg]-butadiene monoepoxide, 8, has been synthesized2 by treating the water solution (pH 5.5) of magnesium monoperoxyphthalate hexahydrate at room temperature with [Dg]-1,3-butadiene at 1 atmosphere in 94% yield after 50 min reaction time. Under these conditions less than 1% of butadiene diepoxide has been formed as determined by GC/MS. The concentration of the [Dg]-butadiene monoepoxide in the aqueous reaction mixture at various reaction times has been determined by selective ion monitoring of ions with mjz... 

A solution of 5 mmol of the hydrazone in 5 mL of methanol is added dropwise to 6 mmol of magnesium monoperoxyphthalate hexahydrate suspended in 40 mL of a mixture of methanol and pH 7 phosphate buffer solution (1 1) at 0°C. The reaction mixture is stirred at 0"C until the hydrazone has completely reacted (monitored by TLC). 150mL of diethyl ether and 10 mL of water are added, and the organic layer is separated and washed with lOmL of sat. aq NaHC03,10 mL of water and 10 mL of brine. The ethereal solution is dried over MgS04 and concentrated at reduced pressure. The crude product is purified by Kugelrohr distillation or flash chromatography to afford the alkylated ketones in 76 99% yield without any racemization. 

In the original patent published by Merck in 1995, rofecoxib (2) was synthesized in three steps from the known 4-(methylthio)acetophenone (10), prepared from the Friedel-Crafts acylation of thioanisole. As depicted in Scheme 2, oxidation of sulfide 10 using an excess of magnesium monoperoxyphthalate hexahydrate (MMPP, an inexpensive, safe and commercially available surrogate for w-CPBA) gave rise to sulfone 11, which was subsequently brominated with bromine and AICI3 to afford 2-bromo-l-(4-(methylsulfonyl)phenyl)ethanone (12). After recrystallization from 1 1 EtOAc/hexane, the pure phenylacyl bromide 12 was then cyclo-condensed with phenylacetic acid under the influence of l,8-diazabicyclo[5.4.0]undec-7-ene (DBU) to deliver rofecoxib (2) in... 

The synthesis of rofecoxib can be achieved by several different routes (Drugs Fut., 1998). A highly efficient synthesis for rofecoxib was recently described (Therien et al., 2001). As illustrated in Scheme 79, acetophenon (i) is prepared according to the literature, by Friedel-Crafts acylation with thioanisole. Oxidation with MMPP (magnesium monoperoxyphthalate hexahydrate) affords the sulfone (ii), which is reacted with bromine in chloroform in the presence of a trace amount of AICI3, to give (iii). Bromoketone (iii) is than coupled and cyclized in a second step, one-pot procedure with phenylacetic acid. Firstly, the mixture of bromoacetophenone (iii) and phenylacetic acid in acetonitrile is treated with... 

Using urea-hydrogen peroxide with trifiuoroacetic anhydride cubane derivatives can undergo tris-Bayer Villiger reactions in good yield. This reaction can be accomplished with the use of MCPBA, however, the reaction was not successful when magnesium monoperoxyphthalate hexahydrate (MMPP) was used as the oxidation reagent. 

The three best known preformed peracids are DPDA (diperoxydodecanoic acid), H48 (magnesium monoperoxyphthalate hexahydrate), and PAP (phthalimidoperoxycaproic acid) (Fig. 11). The former two have been produced on semicommercial scale. PAP is very slow to biodegrade and has low solubility [20]. 

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