Oxidation with manganic acetate

The oxidation of thebaine with manganic acetate first gives [xvi], which on hydrolysis with 20 per cent, hydrochloric acid affords after three minutes at 100° C. the dihydroxyketone [xvrr], and 14-hydroxy-codeinone [xvm] after twenty minutes [98]. The 14-substituted codeinones are discussed in Chapter XVIII. 

Hydroxycodeinono has also been prepared by the oxidation of thebaine with sodium diohromate in aqueous acetic acid or sulphuric aoid [3-5, 10-11], Tho oxidation of thobaino with manganic acetate gives 8- (or J4-) aootyl- 8 14-diliydroxydihydrothobaino [vi], which can... 

An interesting example is the oxidation of dimethylaniline (39). Oxidation of (39) with manganic acetate in acetic acid gives as the sole isolable product 4,4 -bis(dimethylamino)diphenylethane (40). Apparently the first step in the reaction is dealkylation by the mechanism of equation (7.69),... 

This is a way to do this procedure without having to use one of those crazy tube furnaces stuffed with thorium oxide or manganous oxide catalyst [21]. The key here is to use an excess of acetic anhydride. Using even more than the amount specified will insure that the reaction proceeds in the right direction and the bad side reaction formation of dibenzylketone will be minimalized (don t ask). 18g piperonylic acid or 13.6g phenylacetic acid, 50mL acetic anhydride and 50mU pyridine are refluxed for 6 hours and the solvent removed by vacuum distillation. The remaining residue is taken up in benzene or ether, washed with 10% NaOH solution (discard the water layer), and vacuum distilled to get 8g P2P (56%). 

The present research was focused on the study of acetaldehyde oxidation rising air with aqueous mangan acetate catalyst in mechanically stirred tank reactor. 

Cyclopentanone has been prepared from adipic acid by distilling the calcium salt,1 heating alone 2 or with acetic anhydride,3 or in the presence of various catalysts such as barium hydroxide,4 thorium oxide,5 manganous oxide,5 uranium nitrate,6 ferrous sulfate 6 and others.7... 

Commercially available Mn(OAc)3 2H20 has been used for most oxidative cyclizations. This reagent can also be prepared easily from potassium permanganate and manganous acetate in acetic acid [1], Anhydrous Mn(OAc)3 is slightly more reactive than the dihydrate. Reaction times with the anhydrous reagent are usually somewhat shorter but the yields of products are usually comparable. Both tri-fluoroacetic acid and potassium or sodium acetate have been used with Mn(OAc)3. 

Manganic acetate (manganese triacetate), Mn(OCOCH3)3, is prepared by refluxing a solution of manganese acetate tetrahydrate in acetic acid with potassium permanganate [S03]. This oxidant hydroxylates ben-zylic methylene groups [416] and forms lactones from terminal alkenes [803, 804] (see equation 88). 

In this process, a mixture of phenylacetic acid and glacial acetic acid is slowly dripped into a Pyrex combustion tube which is filled with pea-sized pumice stones covered with a coating of either thorium oxide or manganous oxide catalyst. This bed of catalyst is heated to a high temperature with a tube furnace and the vapors of phenylacetic acid and acetic acid react on the surface of the catalyst to produce ketones. Three reactions result. 

Dihydrofumnes. Dihydrofuranes are obtained in fair to high yield by reaction of readily enolizable ketones (/3-diketones, /3-keto esters) with olefins in the presence of 2 eq. of manganic acetate. The reaction is considered to involve generation and oxidation of free radicals. 

When treated with manganous sulfate and sulfuric acid, bromates give a red color initially, due to the intermediate formation of Mn sulfate. On boiling, or better on addition of alkali acetate, a precipitate of brown hydrated manganese oxide is formed ... 

Barek J, Berka A, Pokorna A (1979) Oxidation of organic substances with manganese(lll). Compounds XII. Oxidation of citric acid hexaaquamanganese(II) ion in a noncomplex perchloric acid medium. Coll Czechoslov Chem Comm 44 2603-2611 Prasad G (1965) A kinetic study of redox system containing citric acid and manganic acetate. Bull Chem Soc Jpn 38 882-883... 

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