Acetic acid ketones

Methyl ethyl Acetic acid ketone ethyl ester... 

R = PhCHj, R2 = R3 = H R = Me, R" = H, R = NHAc) lost the thiol and produced the corresponding 2-hydroxycarbazoles (230) on treatment with p-toluenesulfonic acid in acetonitrile." Similarly the thioacetal 231 lost 1-mol equivalent of thiol and one of water, giving carbazole 232 in acetic acid. Ketone 233 gave the lactone 234 on dehydration with p-toluenesul-... 

It is apparent that if one wishes to obtain pure chemicals by biomass pyrolysis, further processing to separate the reaction mixture is necessary. As will be shown later, this did not hinder commercial use of biomass pyrolysis for the manufacture of specific chemicals. The slow, destructive distillation of biomass was commercial technology for the production of several commodity chemicals long before fossil fuels became the preferred feedstocks. Hardwood pyrolysis once served as an important commercial source of methanol, acetic acid, ketones, and other chemicals. 

Platinum oxide acetic acid Ketones from a,y -ethyIeneketones... 

Chromium trioxide I acetic acid Ketones from hydrocarbons... 

Salicylaldehyde/acetic acid Ketones from hydrazones s. 31,343... 

Neoprene is affected or attacked by strong oxidizing acids, acetic acid, ketones, esters, and chlorinated and nitro hydrocarbons. 

Since hydroxylamine is usually available only in the form of its salts, e.g., the hydrochloride or sulphate, the aqueous solution of these salts is treated with sodium acetate or hydroxide to liberate the base before treatment with the aldehyde or ketone. Most oximes are weakly amphoteric in character, and may dissolve in aqueous sodium hydroxide as the sodium salt, from which they can be liberated by the addition of a weak acid, e.g., acetic acid. 

It follows therefore that ethyl malonate can be used (just as ethyl aceto- acetate) to prepare any mono or di-substituted acetic acid the limitations are identical, namely the substituents must necessarily be alkyl groups (or aryl-alkyl groups such as CjHjCHj), and tri-substituted acetic acids cannot be prepared. Ethyl malonate undergoes no reaction equivalent to the ketonic hydrolysis of ethyl acetoacetate, and the concentration of the alkali used for the hydrolysis is therefore not important. 

The Fischer Indolisation Reaction occurs when the phenylhydrazone of a suitable aldehyde or ketone undergoes cyclisation with loss of ammonia, under the influence of various reagents, such as zinc chloride, ethnnolic hydrogen chloride, or acetic acid. For example, the phenylhydrazone of acetophenone (p. 257) when heated with zinc chloride gives 2 phenylindole. ... 

Acetic acid n.But3rric acid Methyl n-propyl ketone... 

Small quantities of the sjunmetrical ketones (CHjjjCO and (CHjCHjCHjjjCO (di-n-propyl ketone) are formed as by-products these can easily be removed by fractional distillation through an efficient column. An excess of the cheaper reagent, acetic acid, is employed the resulting acetone is readily removed by washing with water and little di-n-propyl ketone is formed under these conditions. 

Ketonic hydrolysis with a mixture of sulphuric and acetic acids of the ethyl Mobutyryltsobutyrate 3uelds di-tso-propyl ketone ... 

Ketonic hydrolysis to di-iso-propyl ketone. Mix 15 g. of the ester with 30 ml. of glacial acetic acid, 10 ml. of water and 10 ml. of concentrated sulphuric acid, and reflux in a flask coimected by a ground glass joint... 

The formation of ethyl isopropylidene cyanoacetate is an example of the Knoevenagel reaction (see Discussion before Section IV,123). With higher ketones a mixture of ammonium acetate and acetic acid is an effective catalyst the water formed is removed by azeotropic distillation with benzene. The essential step in the reaction with aqueous potassium cyanide is the addition of the cyanide ion to the p-end of the ap-double bond ... 

Alternatively, dissolve approximately equivalent amounts of the aldehyde (or ketone) and the solid reagent in the minimum volume of cold glacial acetic acid, and reflux for 15 minutes. The p-nitrophenyl-hydrazone separates on cooling or upon careful dilution with water. 

Steam distil from a 1 - 5 litre three-necked flask until the odour of nitrobenzene is no longer perceptible in the distillate (6-12 hours). Extract the cold residue with three 100 ml. portions of ether, dry the combined extracts with anhydrous magnesium sulphate, and distil oflF the ether. The residue solidifies and consists of almost pure methyl P-naphthyl ketone, m.p. 52° the yield is 30 g. Upon recrystallisation from glacial acetic acid, the m.p. is raised to 54°. 

Acetonylacetone is available commercially as a by-product of the manufacture of acetic acid from acetylene. It may be prepared by condensation of chloroacetone with ethyl sodioacetoacetate the resulting ethyl acetonylacetoacetate when heated with water under pressure at 160° undergoes ketonic scission to give acetonylacetone. 

An important general method of preparing indoles, known as the Fischer Indole synthesis, consists in heating the phenylhydrazone of an aldehyde, ketone or keto-acld in the presence of a catalyst such as zinc chloride, hydrochloric acid or glacial acetic acid. Thus acrtophenone phenylhydrazone (I) gives 2-phenyllndole (I V). The synthesis involves an intramolecular condensation with the elimination of ammonia. The following is a plausible mechanism of the reaction ... 

The solid appears to be a mixture of the complexes CH,COOH.BF, and 2CH COOH.BF,. The latter appears to be a liquid and is alone soluble in ethylene dichloride the former is a solid. The solid moiioocetic acid complex is obtained by saturating an ethylene dichloride solution of acetic acid with boron trifluoride, filtering and washing the precipitate with the solvent it is hygroscopic and should be protected from moisture. It may be used as required 0-75 mol is employed with 0-26 mol of ketone and 0 6 mol of anhydride. 

Add, with stirring, a solution of 6 8 g. of the fiis-diazo ketone in 100 ml. of warm dioxan to a suspension of 7 0 g. of freshly precipitated silver oxide in 250 ml. of water containing 11 g. of sodium thiosulphate at 75°. A brisk evolution of nitrogen occurs after 1 5 hours at 75°, filter the liquid from the black silver residue. Acidify the almost colourless filtrate with nitric acid and extract the gelatinous precipitate with ether. Evaporate the dried ethereal extract the residue of crude decane-1 10-dicarboxylic acid weighs 4 -5 g. and melts at 116-117°. RecrystaUisation from 20 per cent, aqueous acetic acid raises the m.p. to 127-128°. 

Alternatively, treat a solution of 3 9 g. of the 6is-diazo ketone in 50 ml. of warm dioxan with 15 ml. of 20 per cent, aqueous ammonia and 3 ml. of 10 per cent, aqueous silver nitrate under reflux in a 250 or 500 ml. flask on a water bath. Nitrogen is gently evolved for a few minutes, followed by a violent reaction and the production of a dark brown and opaque mixture. Continue the heating for 30 minutes on the water bath and filter hot the diamide of decane-1 lO dicarboxyhc acid is deposited on cooling. Filter this off and dry the yield is 3 -1 g., m.p. 182-184°, raised to 184-185° after recrystallisation from 25 per cent, aqueous acetic add. Hydrolyse the diamide (1 mol) by refluxing for 2-5 hours with 3N potassium hydroxide (4 mols) acidify and recrystaUise the acid from 20 per cent, acetic acid. The yield of decane-1 10-dicarboxyhc acid, m.p. 127-128°, is almost quantitative. 

The following are examples of the above procedure. A mixture of diethylamine and re-butyl alcohol may be separated by adding sufficient dilute sulphuric acid to neutralise the base steam distillation will remove the alcohol. The amine can be recovered by adding sodium hydroxide to the residue and repeating the distillation. A mixture of diethyl ketone and acetic acid may be treated with sufficient dilute sodium hydroxide solution to transform the acid into sodium acetate and distilling the aqueous mixture. The ketone will pass over in the steam and the non-volatile, stable salt will remain in the flask. Acidification with dilute sulphuric acid hberates acetic acid, which can be isolated by steam distillation or by extraction. 

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