Peracetic acid-Sodium acetate

ALLENE OXIDES Peracetic acid-Sodium acetate. 

Selenophene is reported to be little affected by oxidizing agents under mild conditions (B-79MI31600) and tellurophene is reported to be fairly stable to light and air at room temperature (77AHC(21)119). Dibenzoselenophene forms a 5-oxide when treated with peracetic acid in acetic acid, a compound also obtained when the 5,5-dibromide is reacted with dilute aqueous sodium hydroxide (50JA5753). 

Approximately 40% peracetic acid in acetic acid is available (Becco Chemical Division, Food Machinery and Chemical Corporation, Buffalo 7, New York). Sodium acetate is added to neutralize a small amount of sulfuric acid which is present in the commercial product. The peracetic acid concentration should be determined by titration.2 The peracetic acid solution used by the submitters contained 0.497 g. (0.00655 mole) of peracid per... 

Similarly, for an oxidant that contains an indirectly activated oxygen, the preparation method can always be used to determine the oxidant. For example, lodosylbenzene (PhlO), a common oxidant, is made by treatment of the hyperva-lent iodine reagent PhI(OAc)2 with sodium hydroxide. The diacetate is made from the action of peracetic acid and acetic acid on iodobenzene. Thus, the iodosylben-zene oxidant can be traced to hydrogen peroxide, which is used to make the peracetic acid. 

Medroxyprogesterone acetate (74) is stmcturaHy related to and has been prepared from hydroxyprogesterone (39) (Fig. 10). Formation of the bis-ketal accomplishes the protection of the ketones and the required migration of the double bond. Epoxidation with peracetic acid produces a mixture of epoxides (75), with a predominating. Treatment of the a-epoxide with methyl magnesium bromide results in diaxial opening of the epoxide. Deprotection of the ketones provides (76), which is dehydrated to (77) by treatment with dilute sodium hydroxide in pyridine. Upon treatment with gaseous hydrochloric... 

Methylpyridine-l-oxide has been prepared by the oxidation of 3-methylpyridine with hydrogen peroxide in glacial acetic acid, with 40% peracetic acid and sodium acetate, and with per benzoic acid in benzene. ... 

Commercial 40% peracetic acid (containing 1% sulfuric acid) may be employed for this reaction. However, it is necessary to neutralize the sulfuric acid with sodium or potassium acetate to prevent further reactions. 

A solution of 17-cyanoandrosta-5,16-dien-3jS-ol acetate (46 g) and anhydrous potassium acetate (0.46 g) in methylene dichloride (310 ml) is treated with a mixture of 40% peracetic acid (37 ml) and anhydrous potassium acetate (1.84 g) in methylene dichloride (46 ml), the temperature of the solution being maintained below 25°. The mixture is stored at room temperature for 4 hr and then washed successively with water, 5% sodium bicarbonate solution (aqueous sodium bisulfite, 10g/150g water, has been used to decompose excess reagent before workup) and water until neutral. Evaporation of the dried solution and addition of ether gives 24.1 g of 5oc,6a-epoxy-17-cyanoandrost-16-en-3 -ol acetate mp 187-190°. One recrystallization from methanol gives 20.4 g of oxirane melting at 191-194°. 

Preparation of 5a,6a-0xido-17a-Hydroxya//opregnane-3,20-dione 3,20-Bis-(Ethy ene Ketal) A solution was prepared by heating 19.96 g (0.0477 mol) of 17a-hydroxyprogesterone 3,20-bis-(ethylene ketal) and 500 ml of benzene. After the solution was effected the flask was cooled to 5°C and a mixture of 3.68 g (0.0449 mol) of sodium acetate and 174 ml of 40% peracetic acid was added with stirring. The reaction mixture was stirred in the ice bath for 3 hours. The lower peracid layer was separated, diluted with water and extracted twice with benzene. 

However, peracetic acid does appear to be a suitable inexpensive substitute for MCPBA. Treatment of 275 mg (1.40 mmol) of VII with 0.40 ml (2.1 mmol) of 35% peracetic acid (FMC Corporation) containing 32 mg of sodium acetate afforded 283 mg (95%) of product consisting of ca. 75% VIII and 25% IX. 

To 136 g A4 carene in 330 ml methylene chloride and 120 g anhydrous sodium acetate, add dropwise with vigorous stirring ir an ice bath, 167 g of 50% peracetic acid and continue stirring for ten hours. Heat to boiling for two hours, cool, wash with water, sodium carbonate, water, and dry, evaporate in vacuum the methylene chloride to get about 100 g p-menthadieneol. Apparently (CA... 

A solution of 2 gm (0.014 mole) of 3-nitroaniline in 40 ml of glacial acetic acid and 1.85 gm (0.028 mole) of peracetic acid is treated with 1 ml of an aqueous solution containing 5 mg of cupric chloride dihydrate. The reaction mixture is stirred for 16 hr at 17°C. After this time, the precipitated product is filtered off (0.8 gm). The mother liquor is added to 200 ml of a 3N sodium hydroxide solution, whereupon another 0.61 gm of product is precipitated. The crude products are combined yield 1.42 gm (72%), m.p. 140°-144°C. On recrystallization the melting point is raised to 144°-147°C. 

Behind a shield, peracetic acid is prepared by adding dropwise to 20 ml of rapidly stirred methylene chloride, 3 ml (0.11 mole) of 90% hydrogen peroxide, and 1 drop of sulfuric acid followed by 13.5 gm (0.132 mole) of acetic anhydride over a 10 min period while maintaining the mixture at 0°C. Then the mixture is stirred at room temperature for 15 min, and to the clear solution is added 0.5 gm of sodium acetate (to neutralize the acid catalyst.)... 

To a solution of 4-(4-chlorophenyl)but-l-ene in dichloromethane was added dropwise with stirring a mixture of 40% peracetic acid and sodium acetate. 

Peracetic acid solution (107.7 g of 9.0 wt % peracetic acid) at ambient temperature was added to a reaction flask equipped with mechanical stirrer and thermocouple, nitrogen inlet adapter and addition funnel. A 20 wt % stock solution of the dienolsilyl ether of codeinone (41.7 g) was added through the addition funnel over a period of about 5 min and the temperature of the contents maintained at 28°C. The batch was stirred at 22°C for at least 3 hours. In order to test reaction completeness, a small sample was withdrawn from the batch and quenched with saturated sodium bicarbonate solution, and extracted with ethyl acetate. The EtOAc layer was spotted onto a TLC plate and subsequently checked for the disappearance of starting dienolsilyl ether of codeinone. The TLC mobile phase was a mixture of 95 5 of dichloromethane and methanol plus 3-5 drops of concentrated ammonium hydroxide. If the reaction was adjudged incomplete, the mixture was stirred at the same temperature for an additional 2 hours then analyzed by TLC again. Alternatively completion of the reaction was pushed by the addition of 10 g of peracetic acid (9.0 wt %) and stirring for an additional 1 h (analysis was then once more performed using TLC). 

Although several methods are available for the preparation of the title compounds, in practice the starting material is (diacetoxyiodo)benzene (DIB). The standard method for its preparation is direct oxidation of iodobenzene with either peracetic acid [ 1 ] or sodium perborate in acetic acid [2], The first method appears to be preferable it requires great care in maintaining temperature at exactly 40°C at a lower... 

A stirred mixture of acetic anhydride (305 ml) and 30% hydrogen peroxide (70 ml) was kept at exactly 40°C for 4 h the use of a thermostated bath is strongly recommended. To the resulting peracetic acid solution, iodobenzene (52 g, 28.5 ml) was added with stirring over 15 min and the clear reaction mixture was kept overnight at room temperature. A part of DIB crystallized out and was collected then ice-water ( 400 ml) was added to the filtrate and a further crop of crystals was obtained. The combined material was washed with cold water and petroleum ether and was dried in a desiccator over sodium hydroxide to yield 55-65 g (67-79%) of crude DIB, m.p. 156-159°C (recrystallized from chloroform, m.p. 163-165°C) this purity is satisfactory in most cases. 

---