Peroxyphthalic acid

Treatment of either cis- or rrans-stilbene-2-carboxylic acids with chlorine or bromine leads to 4-halogeno-3,4-dihydro-3-phenylisocoumarins (58T<4)393). The reactions are stereospecific and are thought to involve intramolecular attack by the carboxyl group on a halonium ion. Ring closure to the corresponding 4-hydroxy compound also occurs stereo-specifically using peroxyphthalic acid (59JOC934). 

Sodium in liquid ammonia does the reduction and the more substituted, and hence more nucleophilic, alkene reacts with the peroxyacid to give the target molecule.12 Peroxyphthalic acid 71 was used as the oxidant. 

Redinger (1961) has reported a value for the carbon-carbon double bond content of alkali lignin based on reaction with peroxyphthalic acid. The procedure is not described or referenced in the article. 

Another dicarboxylic peroxy acid, peroxyphthalic acid, is used for the Baeyer-Villiger reaction of p-diketones and a-keto esters [334]. Besides peroxy acids, ceric ammonium nitrate oxidizes 2-adamantanone to 2-oxa-homoadamantanone in aqueous acetonitrile in 73% yield at 60 °C after 3 h [422]. Tetracyclone (2,3,4,5-tetraphenyl-2,4-cyclopentadien-l-one) is oxidized by ceric ammonium nitrate in aqueous acetonitrile to tetraphenyl-2-pyrone in 77% yield [422]. 

In a-ionone, peroxybenzoic acid and peroxyphthalic acid epoxidize solely the endocyclic double bond to give 3,4-epoxy-a-ionone in 96.5 and 66% yields, respectively [299]. Alkaline hydrogen peroxide, on the other hand, epoxidizes only the double bond conjugated with carbonyl to give a 28-31% yield of a-ionone-ot, p -epoxide [332] (equation 440). 

The oxidation of p-diketones and p-keto esters with peroxyacetic acid [270] and peroxyphthalic acid [333] leads to complex products that ultimately undergo hydrolysis. In the case of acetylacetone, the products are acetic acid and pyruvic acid [270] (equation 452). 

Methyl-4,5-dihydrothiophene-3-carboxylic acid yields the corresponding sulfoxide on treatment with peroxyphthalic acid and the sulfone on refluxing with hydrogen peroxide in acetic acid (equation 560) [16S. Neither oxidant affects the double bond under the conditions used. 

Hexylketene diethylmercaptole is oxidized with peroxyphthalic acid to l,l-bis(ethanesulfonyl)-l-octene (equation 573) [33. ... 

MacDonald and H. O. L. Fischer372 oxidized D-glucose diethyl dithioacetal pentaacetate (24) and its D-manno isomer with mono-peroxyphthalic acid in ether, isolating not the epimeric disulfones but a common product, to which they assigned the structure 3,4,5,6-tetra- O - acetyl -1,2- dideoxy-1,1 -bis (ethylsulfonyl)-D-arabtno-hex-1-enitol (176). Ammonolysis of 176 and reacetylation afforded 177, which was also prepared by oxidation of 2-acetamido-3,4,5,6-tetra-0-acetyl-2-deoxy-D-glucose diethyl dithioacetal, whereas the action of hydrazine in methanol on 176 produced a retroaldol reaction (and saponification) affording D-arabinose (179, 40% yield) and bis(ethyl-sulfonyl)methane (178). The latter reaction accords with earlier ob-... 

The oxidation of pyrido[3,4-r/]pyrimidine with peroxyphthalic acid does not give an A-oxide, pyrido[3,4-i7]pyrimidin-4(3//)-one is obtained instead.472... 

Direct oxidation of quinazolines is less explored than for pyrimidines. 4-Alkoxyquinazolines form A-oxides in moderate yields with peroxyphthalic acid [Pg.120]

A solution of sodium carbonate (62 g, 0.50 mole) in water (250 ml) is placed in a 1-1 flask fitted with a stirrer and thermometer and cooled in ice-salt to 5°C, whereupon 30% hydrogen peroxide (70 g, 0.6 mole) is added in one portion. This mixture is cooled to 0° and treated with finely powdered and sieved phthalic anhydride (75 g, ca. 0.5 mole), then stirred rapidly at — 5° to 0° for 30 min or until almost all the anhydride has dissolved. Next the solution is treated in a separatory funnel with ether (350 ml) and shaken with a cold solution of concentrated sulfuric acid (30 ml) in water (150 ml), then extracted three times with ether (150 ml portions). The ether extracts are united, washed with 40 % ammonium sulfate solution (200 ml), and dried overnight in the ice-chest over anhydrous magnesium sulfate (50 g). The content of peroxyphthalic acid is determined by titration. The yield is 78% (calculated on phthalic anhydride). 

Peroxyphthalic acid Baeyer-Villiger oxidation Carboxylic acid esters from ketones... 

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