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Acetic anhydride with acetals

Acetic anhydride with acetic acid has also been used to acetylate reactive alkylbenzenes like mesltylene, equation 2. In this case, the yield of the product was 72%. [Pg.45]

The nitration of phthalic anhydride with a mixture of concentrated sulphuric and nitric acids yields a mixture of 3-nitro- and 4 nitro phthalic acids these are readily separated by taking advantage of the greater solubility of the 4 nitro acid in water. Treatment of 3 nitrophtlialic acid with acetic anhydride gives 3 nitrophthahe anhydride. [Pg.966]

Acetylation of the amine may also be effected by boiling with 20 ml. of glacial acetic acid and 14 ml. of acetic anhydride for 15-20 minutes, followed by decomposition of the excess of anhydride with water and, after boiling for 5 minutes, poirring with stirring into about 75 ml. of water the product is appreciably coloured. [Pg.998]

Most correlations of rates with localisation energies have used values for the latter derived from the Hiickel approximation. More advanced methods of m.o. theory can, of course, be used, and fig. 7.1 illustrates plots correlating data for the nitration of polynuclear hydrocarbons in acetic anhydride -" with localisation energies derived from self-... [Pg.133]

Methyiaminoacetonitrile (216) reacts with carbon disulfide in the presence of acetic anhydride with ethyl acetate as solvent to give 2-thio-3-methyl-A-4-thiazoline in 74% yield (Scheme 113a) (326). If the reaction is carried out using benzaldehyde in place of acetic anhydride, the corresponding 5-benzylideneamino derivative of 217 is obtained in 70% yield. [Pg.287]

Attempts to use acetic-formic anhydride with Friedel-Crafts catalysts resulted only in acetylation. However, using anhydrous HF as a catalyst, a small amount of aldehyde is also formed in accordance with the fact that acetic—formic anhydride gives both acetyl and formyl fluoride with HF. By continuous removal of the low boiling HCOF, the reaction can be shifted to the formation of this compound (118). [Pg.559]

Various processes involve acetic acid or hydrocarbons as solvents for either acetylation or washing. Normal operation involves the recovery or recycle of acetic acid, any solvent, and the mother Hquor. Other methods of preparing aspirin, which are not of commercial significance, involve acetyl chloride and saHcyHc acid, saHcyHc acid and acetic anhydride with sulfuric acid as the catalyst, reaction of saHcyHc acid and ketene, and the reaction of sodium saHcylate with acetyl chloride or acetic anhydride. [Pg.291]

Uses ndReactions. The Prins reaction of 3-carene with formaldehyde in acetic acid gives mainly 2-carene-4-methanol acetate, which when saponified produces the 2-carene-4-methanol, both of which are commercial products of modest usage (60). 3-Carene (28) also reacts with acetic anhydride with a catalyst (ZnCl2) to give 4-acetyl-2-carene (29) (61), which is also a commercial product. Although 3-carene does not polymerize to produce terpene resins, copolymerization with phenol has been successfully commercialized by DRT in France (62). [Pg.414]

Cellulose esters of aromatic acids, aUphatic acids containing more than four carbon atoms and aUphatic diacids are difficult and expensive to prepare because of the poor reactivity of the corresponding anhydrides with cellulose Httle commercial interest has been shown in these esters. Of notable exception, however, is the recent interest in the mixed esters of cellulose succinates, prepared by the sodium acetate catalyzed reaction of cellulose with succinic anhydride. The additional expense incurred in manufacturing succinate esters is compensated by the improved film properties observed in waterborne coatings (5). [Pg.249]

These can be prepared as for the benzoates using either acetic anhydride with 3N NaOH or acetyl chloride in pyridine. They are hydrolysed as described for the benzoates. This hydrolysis can also be carried out with aqueous 10% NaOH solution, completion of hydrolysis being indicated by the complete dissolution of the acetate in the aqueous alkaline solution. On steam distillation, acetic acid also distils off but in these cases the phenols (see above) are invariably solids which can be filtered off and recrystallised. [Pg.59]

In a typical process for manufacture on a commercial scale bleached wood pulp or cotton linters are pretreated for 12 hours with 40-50% sulphuric acid and then, after drying, with acetic acid. Esterification of the treated cellulose is then carried out using a mixture of butyric acid and acetic anhydride, with a trace of sulphuric acid as catalyst. Commercial products vary extensively in the acetate/ butyrate ratios employed. [Pg.628]

This method is an adaptation of that of Dengel. -Methoxy-phenylacetonitrile can also be prepared by the metathetical reaction of anisyl chloride with alkali cyanides in a variety of aqueous solvent mixtures by the nitration of phenylaceto-nitrile, followed by reduction, diazotization, hydrolysis, and methylation 1 by the reduction of ct-benzoxy- -methoxy-phenylacetonitrile (prepared from anisaldehyde, sodium cyanide, and benzoyl chloride) and by the reaction of acetic anhydride with the oxime of -methoxyphenylpyruvic acid. ... [Pg.52]

The selectivity is probably impaired by bromination at C-2 and C-9. Bromination under buffered conditions of the A -enol acetate prepared from acetic anhydride with perchloric acid catalysis may give better results. See also ref. 55 for a similar bromination. [Pg.290]

Schotfev-Bauviann reaction (p. 209).—This maybe applied to tile pure phenol in order to obtain the benzoyl deiii ative, and the melting-point deteimined, or the acetyl deri -ative maybe pie-pared by boiling for a minute with acetic anhydride with the same object. [Pg.329]

These Br nsted-type plots often seem to be scatter diagrams until the points are collated into groups related by specific structural features. Thus, p-nitrophenyl acetate gives four separate, but parallel, lines for reactions with pyridines, anilines, imidazoles, and oxygen nucleophiles.Figure 7-4 shows such a plot for the reaction of trans-cmmm c anhydride with primary and secondary aliphatic amines to give substituted cinnamamides.All of the primary amines without substituents on the a carbon (R-CHi-NHi) fall on a line of slope 0.62 cyclopentylamine also lies on this line. If this line is characteristic of normal behavior, most of the deviations become qualitatively explicable. The line drawn through the secondary amines (slope 1.98) connects amines with the structure R-CHi-NH-CHi-R. The different steric requirements in the acylation reaction and in the model process... [Pg.350]

It was found inadvisable to use more than four molecules of form-amide [ (47) when R = H] per molecule of anthranilic acid and the condensation produces best results when the mixture is heated at 120 -130°C for 2 hr followed by further heating at 170°-180 C for 2 hr. Other variants of this reaction involve the use of ammonium o-acylaminobenzoates, anthranilic acid in the presence of nitriles and acetic anhydride, o-acetamidonitrile with acetic anhydride or hydrogen peroxide, anthranilic esters and aliphatic or aromatic amides or amidines, isatoic anhydride with amides or amidines, and anthranilic esters with aryl iminochlorides in acetoned The mechanism proposed by Bogert and Gotthelf has had experimental supporR and is represented in Scheme 12. [Pg.292]

Normal Fischer esterification of tertiary alcohols is unsatisfactory because the acid catalyst required causes dehydration or rearrangement of the tertiary substrate. Moreover, reactions with acid chlorides or anhydrides are also of limited value for similar reasons. However, treatment of acetic anhydride with calcium carbide (or calcium hydride) followed by addition of the dry tertiary alcohol gives the desired acetate in good yield. [Pg.62]

Anthracene and maleic anhydride with aluminum chloride give the adduct quantitatively in minutes. The product is recrystallized from ethyl acetate, mp 262-263°. [Pg.74]

Reactions in acetic anhydride with metal acetates present probably occur by 1,4-addition of bromonium acetate (85CHE458). When NBS in sulfuric acid at 20°C was used, the product ratio resembled that observed with bromine-sulfuric acid-silver sulfate. At 60°C the ratio changed to 2 1.2 1 as a consequence of more extensive dibromination (88CHE892) (Scheme 33). As might have been deduced, 2-(2 -thienyl)quinoline was brominated only in the thiophene ring (82CHE28). [Pg.290]

There are many methods for the preparation of ethane-1-hydroxy-1,1-diphosphonic acid including reacting phosphorus trichloride and acetic acid in the presence of tributylamine [106], phosphorus with acetic acid and oxygen [108], acetic anhydride with phosphorous acid and acetyl chloride [80,84-86,109,110], and acetic anhydride with phosphoric acid and acetic acid [111]. By another method ketene and phosphorous acid can be used [112], as shown in Eq. (68) ... [Pg.576]

The Diels Alder reactions of maleic anhydride with 1,3-cyclohexadiene, as well the parallel reaction network in which maleic anhydride competes to react simultaneously with isoprene and 1,3-cyclohexadiene [84], were also investigated in subcritical propane under the above reaction conditions (80 °C and 90-152 bar). The reaction selectivities of the parallel Diels-Alder reaction network diverged from those of the independent reactions as the reaction pressure decreased. In contrast, the same selectivities were obtained in both parallel and independent reactions carried out in conventional solvents (hexane, ethyl acetate, chloroform) [84]. [Pg.287]

C15H21NO5) see Gusperimus trihydrochloride 4-[hydroxy[5-[[(phenylmethoxy)carhonyl]amino]pen-tyl]amino]-4-oxobutanoic acid (C,7H24N20ft 106410-46-2) see Deferoxamine D-a-(4-hydroxyphenyl)-tx-(2-methoxycarbonyl-l-methyl-cthenylamino)acetic acid anhydride with monoethyl carbonate... [Pg.2399]

The effect of incorporating p-hydroxybenzoic acid (I) into the structures of various unsaturated polyesters synthesised from polyethylene terephthalate (PET) waste depolymerised by glycolysis at three different diethylene glycol (DEG) ratios with Mn acetate as transesterification catalyst, was studied. Copolyesters of PET modified using various I mole ratios showed excellent mechanical and chemical properties because of their liquid crystalline behaviour. The oligoesters obtained from the twelve modified unsaturated polyesters (MUP) were reacted with I and maleic anhydride, with variation of the I ratio with a view to determining the effect on mechanical... [Pg.31]

OS 8[ [R 25] [P 6] The acylation of acetic anhydride with various amines was investigated all yields ranged from 75 to 100% with the exception of one value of 46% [83]. The lowest yield was obtained for 1-naphfhylamine and the highest for 1-hexylamine. Throughputs were from 3.8 to 68.3 g... [Pg.428]

The reaction of acetic anhydride with glycerol in the presence of phosphoryl trichloride as a catalyst was carried out the following way ... [Pg.329]

The first compounds of this class46 have been obtained via Route A. The initial condensation of phthalic anhydride with dimethylaniline requires a Friedel-Crafts catalyst, while condensation of the resulting benzophenone with the indole requires acetic anhydride. For Route B preparation of the intermediate l,2-dimethyl-3-(2-carboxybenzoyl)indole has also been described47 by condensation of the two components in the presence of aluminum chloride. However, in our experience, aluminum chloride is, in this case, unnecessary, thus rendering this route the method of choice. [Pg.104]

Heating pyridine-2,3-dicarboxylic acid anhydride with l-ethyl-2-methylindole has been claimed to yield solely the pyridine-2-carboxylic acid, albeit in low yield. This then clearly reacts with Af,A/-diethyl-3-toluidine in acetic anhydride to give the 7-azaphthalide. This is surprising in view of a later report70 in which a one-pot process has been described. Heating pyridine-2,3-dicarboxylic anhydride, prepared in situ, with the indole and subsequent reaction with 3-/V,/V-diethylamino-phenetol under identical conditions to those used in Scheme 8 (but without intermediate isolations) produced a 20 1 mixture of the 4- and 7-azaisomers 16 and 17. It appears that in the previous report the major intermediate isomer, the pyridine-3-carboxylic acid, has not been isolated. [Pg.109]

Introduction of two diaminophenylethylene moieties at the 3-position of the phthalide ring naturally also produces color formers exhibiting infrared absorption. As in Section 4.6.1, the first report93 encompasses a vast number of compounds such as 22 which was prepared by treating phthalic anhydride with 2 mol of 1,1-bisdimethylaminophenylethylene in acetic anhydride. [Pg.114]

Peracetic acid is produced in equilibrium with acetic acid by the reaction of acetic anhydride with hydrogen peroxide, as in Scheme 10.37. Alternatively, peracetic acid can be produced by acid-catalysed oxidation of acetic acid with hydrogen peroxide, as in Scheme... [Pg.140]


See other pages where Acetic anhydride with acetals is mentioned: [Pg.41]    [Pg.227]    [Pg.295]    [Pg.496]    [Pg.229]    [Pg.518]    [Pg.322]    [Pg.72]    [Pg.1091]    [Pg.150]    [Pg.541]    [Pg.307]    [Pg.691]    [Pg.34]    [Pg.118]    [Pg.105]    [Pg.77]    [Pg.183]    [Pg.203]    [Pg.118]    [Pg.384]    [Pg.132]   
See also in sourсe #XX -- [ Pg.599 ]




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2,3-Dimethylpyrazine 1,4-dioxide with acetic anhydride

2,5-Dimethylpyrazine 1-oxide with acetic anhydride

2- Picoline reaction with acetic anhydride

3-Methoxycarbonylpyrazine 1-oxide with acetic anhydride

Acetic acid anhydride, reaction with radical

Acetic acid, anhydride protection with

Acetic anhydride Friedel-Crafts reaction with

Acetic anhydride acetyl phosphate preparation with

Acetic anhydride esterification with

Acetic anhydride reaction with amines

Acetic anhydride reaction with benzaldehyde

Acetic anhydride reaction with ethylene glycol

Acetic anhydride reaction with water

Acetic anhydride with alcohols

Acetic anhydride with amines

Acetic anhydride with arylamines

Acetic anhydride with ethers

Acetic anhydride with glycine

Acetic anhydride with phenols

Acetic anhydride with salicylic acid

Acetic anhydride with sucrose

Acetic anhydride with sulfoxides

Acetic anhydride, acetylation of gluconolactone with

Acetic anhydride, acylation with

Acetic anhydride, condensation with

Acetic anhydride, condensation with 2-phenyl-5-oxazolone

Acetic anhydride, condensation with and acetylation of glycine

Acetic anhydride, condensation with in cyclization of hippuric acid

Acetic anhydride, condensation with in cyclization of o-formylphenoxyacetic acid to coumarone

Acetic anhydride, electrostatic reaction with alcohols

Acetic anhydride, electrostatic reaction with amines

Acetic anhydride, incompatibilities with

Acetic anhydride, reaction with amino

Acetic anhydride, reaction with ethanol

Acetic anhydride, trifluororeactions with boron-stabilized carbanions

Acetic anhydride, trifluororeactions with boron-stabilized carbanions synthesis of alkenes

Acetic anhydride, with 2-heptanone

Acetic anhydride, with 2-heptanone give 3-n-butyl-2,4-pentanedione

Acetic anhydride, with 2-heptanone give 3-„-butyl-2,4-pentanedione

Acetic anhydride: acetylation with

Acetic anhydride: acetylation with physical properties

Acetylation with acetic anhydride and

Acylation of glycine with acetic anhydride

Alcohols acetylation with acetic anhydrid

Alcohols estimation with acetic anhydride

Aldehydes condensations with anhydrides, acetic anhydride

Alkenes reaction with acetic anhydride

Aromatic with acetic anhydride

Carbamates with acetic anhydride

Cellulose reaction with acetic anhydride

Cellulose with dimethyl sulfoxide-acetic anhydride

Esterification of alcohol with acetic anhydride using a fluorous scandium catalyst

Ethers cleavage with acetic anhydride

Formylation with acetic formic anhydride

Maleic anhydride/acid copolymer with vinyl acetate

Methylpyrazine 1-oxides with acetic anhydride

Monosaccharide reaction with acetic anhydride

Nitration with acetyl nitrate in acetic anhydride

Pyrazine 1,4-dioxide with acetic anhydride

Pyridine 1-oxide reaction with acetic anhydride

Reaction with acetic anhydride

Reaction with nitric acid-acetic anhydride

Rearrangement with Acetic Anhydride

Screening Method B, including Derivatization with Acetic Anhydride

Selective Ring-opening of Cyclic Acetals with Carboxylic Acid-Trifluoroacetic Anhydride Mixtures

Selective acetylation with acetic anhydride

Selective synthesis of acetophenones in batch reactors through acetylation with acetic anhydride

Selective synthesis of acetophenones in fixed bed reactors through acetylation with acetic anhydride

Sulfoxides reaction with acetic anhydride

With acetic anhydride

With acetic anhydride

With anhydrides

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