Acetic valeric anhydride

Ethanoic pentanoic anhydride (acetic valeric anhydride)... 

Other mixed esters, eg, cellulose acetate valerate [55962-79-3] cellulose propionate valerate [67351-41-17, and cellulose butyrate valerate [53568-56-2] have been prepared by the conventional anhydride sulfuric acid methods (25). Cellulose acetate isobutyrate [67351-38-6] (44) and cellulose propionate isobutyrate [67351-40-0] (45) have been prepared with a 2inc chloride catalyst. Large amounts of catalyst and anhydride are required to provide a soluble product, and special methods of delayed anhydride addition are necessary to produce mixed esters containing the acetate moiety. Mixtures of sulfuric acid and perchloric acid are claimed to be effective catalysts for the preparation of cellulose acetate propionate in dichi oromethane solution at relatively low temperatures (46) however, such acid mixtures are considered too corrosive for large-scale productions. 

Figure 3.1 The reaction of an anhydride with wood, for acetic anhydride (R = CHj) propionic (R = C2Hs), butyric (R = C2Hj), valeric (R = C4H, hexanoic (R = C H-iq) and heptanoic (R = CgH-j ).

A series of oxovanadium(iv) carboxylates V0(RC02)2 (RCO2 = acetate, propionate, butyrate, isobutyrate, valerate, pivalate, phenylacetate, benzoate, or w-chlorobenzoate) have been prepared by the reaction of freshly prepared hydrated V2O4 with a mixture of the corresponding acid and anhydride in toluene or DMF solution, and/or by the reaction of VOCI2 and the corresponding carboxylic acid in aqueous solution. I.r., electronic, and e.s.r. spectra... 

Acetic acid has been found to react with toluene to form p-methylace-tophenone (Simons et al., 49), to react with benzene to form acetophenone, and to react with phenol to form p-hydroxy acetophenone. Acetyl chloride also formed acetophenone with benzene and acetic anhydride reacted with toluene to form both p-methylacetophenone and 2,4-diace-tyltoluene. Valeric acid reacted with toluene to form p-tolyl-n-butyl ketone. Both benzoic acid and benzoyl chloride reacted with toluene to form p-tolylphenyl ketone. Acenaphthene with either benzoic acid or benzoyl chloride gave 3-benzoylacenaphthene (Fieser and Hershberg,... 

A suspension of 300 mg of adriamycin-14-valerate hydrochloride in 20 ml of ethyl acetate was treated with 0.45 ml of trifluoroacetic anhydride in small portions over a few minutes until all solids had dissolved. The solution was mixed immediately with equal portions of water and chloroform (total volume 100 ml). The chloroform layer was separated and washed once with water and twice with pH 7 aqueous buffer. The chloroform solution was dried over sodium sulfate and then was evaporated to dryness under reduced pressure. The residue was dissolved in 25 ml of methanol, and the resulting solution was heated at reflux for 5 minutes, then cooled and evaporated to dryness. The residue was redissolved in 4 ml of chloroform, and the crude product was precipitated by the addition of 20 ml of petroleum ether (b.p. 38°-49°C). The crude material was purified by chromatography on a silicic acid column. 

The specimens were treated according to the method of Nakagami and coworkers [17,18]. Japanese linden Tilia japonica Smik.) was treated with trifluoroacetic acid anhydride and the fatty acids (TFAA method), which included acetic acid, propionic acid, valeric acid, hexanoic acid, decanoic acid, lauric acid, and palmitic acid. Dynamic measurements were made with a torsion pendulum apparatus under a vacuum. An increasing temperature rate was 2°C/min. The amount of introduced side chain per gram of wood is about 4-6 mmol/g [16]. The chemical structure of the treated wood is presented by the formula ... 

By bacterial fermentation the calcium salt of lactic acid is decomposed into salts of simpler acids, e.g,y propionic, bulyric and valeric. As an acid lactic acid yields an ethyl ester with ethyl alcohol and as an alcohol it yields, with acetic anhydride, an acetyl derivative. The latter compound results from the putrefaction of muscular tissue, as this contains both lactic and acetic acid. 

T. Urbanski and Bicrnacki (208) nitrated ethyl n-valerate with nitric acid in glacial acetic acid-acetic anhydride at 23 2 C and found that a ntixture of 2- 3- and 4-nitrovalerates was formed in the ratio 0.5 0.7 l. At 63 2 C a certain amount of l-nitrobutane was formed due to the decarboxylation of the 2-nitrovalerate. 

Horse-radish peroxidase has been treated with acetic, butyric, valeric, enanthic, and succinic anhydrides of mono- and di-carboxylic acids, and with picrylsulphonic acid. ° The effects of these modifications on catalytic activity, rates of irreversible thermal inactivation, and absorption and c.d. spectra were studied. The degree of modification rather than the nature of the modifier was found to be responsible for the major effect on the macromolecular conformation and thermostability of the enzyme after modification. 

Perkin obtained only cinnamic acid from benzaldehyde, acetic anhydride, and either sodium butyrate or sodium valerate instead of sodium acetate but with sodium propionate and propionic anhydride, or sodium butyrate and butyric anhydride, in all cases at i8o°, homologues of cinnamic acid were obtained. He concluded that the salt from which the anhydride is derived must be present, but the reaction is between the aldehyde and the acid anhydride ... 

The chemical imidization method consists of a treatment of a polyamic acid film or powder with dehydrating agents. Acetic anhydride or other lower aliphatic acids, such as propionic, valeric acid or others, can be used for this purpose. Ketenes and dimethyl ketenes can also be used as dehydrating agents. Tertiary amines are used as catalysts for the chemical imidization. The chemical imidization may also be carried out in a solution of the polyamic acid in aprotic solvent") by adding acetic anhydride and tertiary amine. 

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