Acetone substitution

Uses Solvent for nitrocellulose and cellulose acetate artificial flavor for lemonades and essences fungicide and larvacide for cereals, tobacco, dried fruits acetone substitute organic synthesis. 

Scheme 5.2-128 The coupling of acetone substituted benzenes in ionic liquids using ultrasound [278].

Uses Synthetic flavoring agent and fragrance in foods and pharmaceuticals intermediate for prod, of pharmaceuticals and crop protection agents solvent for nitrocellulose, pharmaceuticals insecticide, fungicide, and larvicide for tobacco, cereals, dried acetone substitute org. synthesis disinfectant preservative reagent fragrance in cosmetics... 

Calcium acetate Cumene Cumene hydroperoxide Isopropyl alcohol acetone mfg., pure Acetone sodium bisulfite acetone substitute Ethyl formate acetone synthesis Whey protein acetone, raw materials Molasses (Saccharum officinarum) acetylating agent, agric. chemicals Acetyl chloride acetylating agent, dyes Acetic anhydride acetylating agent, explosives Acetic anhydride... 

Ketonic Hydrolysis. Hot dilute caustic alkalis or hydrochloric acid first hydrolyse off the ethyl group, and then remove carbon dioxide, a mono- or di-substituted acetone being thus obtained ... 

In brief, suitable hydrolysis of ethyl acetoacetate derivatives will give mono-or di-alkyl substituted acetones or acetic acids. Tri-substituted acetones or acetic acids cannot be obtained moreover, the di-substituted acetones must... 

Acetone ethyl methyl ketone diethyl ketone acetophenone, ben-zophenone (and their nuclear-substituted derivatives). Cyclohexanone. 

The more extensive problem of correlating substituent effects in electrophilic substitution by a two-parameter equation has been examined by Brown and his co-workers. In order to define a new set of substituent constants. Brown chose as a model reaction the solvolysis of substituted dimethylphenylcarbinyl chlorides in 90% aq. acetone. In the case ofp-substituted compounds, the transition state, represented by the following resonance structures, is stabilized by direct resonance interaction between the substituent and the site of reaction. 

The suitability of the model reaction chosen by Brown has been criticised. There are many side-chain reactions in which, during reaction, electron deficiencies arise at the site of reaction. The values of the substituent constants obtainable from these reactions would not agree with the values chosen for cr+. At worst, if the solvolysis of substituted benzyl chlorides in 50% aq. acetone had been chosen as the model reaction, crJ-Me would have been —0-82 instead of the adopted value of —0-28. It is difficult to see how the choice of reaction was defended, save by pointing out that the variation in the values of the substituent constants, derivable from different reactions, were not systematically related to the values of the reaction constants such a relationship would have been expected if the importance of the stabilization of the transition-state by direct resonance increased with increasing values of the reaction constant. 

Out first example is 2-hydroxy-2-methyl-3-octanone. 3-Octanone can be purchased, but it would be difficult to differentiate the two activated methylene groups in alkylation and oxidation reactions. Usual syntheses of acyloins are based upon addition of terminal alkynes to ketones (disconnection 1 see p. 52). For syntheses of unsymmetrical 1,2-difunctional compounds it is often advisable to look also for reactive starting materials, which do already contain the right substitution pattern. In the present case it turns out that 3-hydroxy-3-methyl-2-butanone is an inexpensive commercial product. This molecule dictates disconnection 3. Another practical synthesis starts with acetone cyanohydrin and pentylmagnesium bromide (disconnection 2). Many 1,2-difunctional compounds are accessible via oxidation of C—C multiple bonds. In this case the target molecule may be obtained by simple permanganate oxidation of 2-methyl-2-octene, which may be synthesized by Wittig reaction (disconnection 1). 

If one heats acetone and pyrrole in the presence of catalytic amounts of acid, so-called acetone pyrrole is formed in over 80%i yield. This colorless, macrocyclic compound contains four pyrrole units which are connected by dimethylmethylene bridges, ft is formed by electrophilic-a-substitution of pyrrole by acetone, acid-catalyzed oligomerization, and spontaneous. 

Various 4-, 5-, or 4,5-disubstituted 2-aryIamino thiazoles (124), R, = QH4R with R = 0-, m-, or p-Me, HO C, Cl, Br, H N, NHAc, NR2, OH, OR, or OjN, were obtained by condensing the corresponding N-arylthiourea with chloroacetone (81, 86, 423), dichloroacetone (510, 618), phenacyichloride or its p-substituted methyl, f-butyl, n-dodecyl or undecyl (653), or 2-chlorocyclohexanone (653) (Method A) or with 2-butanone (423), acetophenone or its p-substituted derivatives (399, 439), ethyl acetate (400), ethyl acetyl propionate (621), a- or 3-unsaturated ketones (691), benzylidene acetone, furfurylidene acetone, and mesityl oxide in the presence of Btj or Ij as condensing agent (Method B) (Table 11-17). 

Compound 132 condensed with 1 or 2 moles of aliphatic or aromatic a-haloketones in acetonic or alcoholic solution yielded either the corresponding 2-thiazolythiourea (133) (559, 753, 797) or sym-substituted bis(2-thiazolyl)amine (134) (Scheme 64 and Table 11-19) (430, 553, 653). 

Some esters of substituted alcohols have been synthesized by transesterification. Treatment of 4-methyl-5-thiazolecarboxylic acid (14) with 3-chloroethyldiethylamine in acetone in the presence of anhydrous potassium carbonate gives the desired ester (15) in good vield (60%) (Scheme 10) (163). 

The Tokuyama Soda single-step catalyst consists of a zirconium phosphate catalyst loaded with 0.1—0.5 wt % paHadium (93—97). Pilot-plant data report (93) that at 140°C, 3 MPa, and a H2 acetone mole ratio of 0.2, the MIBK selectivity is 95% at an acetone conversion of 30%. The reactor product does not contain light methyl substituted methyl pentanes, and allows MIBK recovery in a three-column train with a phase separator between the first and second columns. 

The solubihty of alkylphenols in water falls off precipitously as the number of carbons attached to the ring increases. They are generally soluble in common organic solvents acetone, alcohols, hydrocarbons, toluene. Solubihty in alcohols or heptane follows the generalization that "like dissolves like." The more polar the alkylphenol, the greater its solubihty in alcohols, but not in ahphatic hydrocarbons likewise with cresols and xylenols. The solubihty of an alkylphenol in a hydrocarbon solvent increases as the number of carbon atoms in the alkyl chain increases. High purity para substituted phenols, through Cg, can be obtained by crystallization from heptane. 

N -Heterocyclic Sulfanilamides. The parent sulfanilamide is manufactured by the reaction of A/-acetylsulfanilyl chloride with excess concentrated aqueous ammonia, and hydrolysis of the product. Most heterocycHc amines are less reactive, and the condensation with the sulfonyl chloride is usually done in anhydrous media in the presence of an acid-binding agent. Use of anhydrous conditions avoids hydrolytic destmction of the sulfonyl chloride. The solvent and acid-binding functions are commonly filled by pyridine, or by mixtures of pyridine and acetone. Tertiary amines, such as triethylamine, may be substituted for pyridine. The majority of A/ -heterocycHc sulfanilamides are made by simple condensation with A/-acetylsulfanilyl chloride and hydrolysis. 

Succinic esters condense with aldehydes and ketones in the presence of bases, eg, sodium alkoxide or piperidine, to form monoesters of alkybdenesuccinic acids, eg, condensation of diethyl succinate with acetone yields ethyl 2-isopropyhdenesuccinate (eq. 3). This reaction, known as Stobbe condensation, is specific for succinic esters and substituted succinic esters (98,99). 

Pure (9-terphenyl can be obtained by fractional distillation. To obtain high purity m- or -terphenyl, the appropriate distillation fraction has to be further purified by recrysta11i2ing, 2one refining, or other refining techniques. Currently, litde demand exists for pure isomers, and only a mixture is routinely produced. Small amounts of acetone, ethanol, or methanol are used to promote dehydrocondensation, and as a result, minor amounts of methyl- or methylene-substituted polyphenyls accompany the biphenyl and terphenyls produced. For most purposes, the level of such products (<1%) is so small that their presence can be ignored. For appHcations requiring removal of these alkyl-polyphenyl impurities, an efficient process for their oxidative destmction has been described (38). 

Cellulose acetate [9004-35-7] is the most important organic ester because of its broad appHcation in fibers and plastics it is prepared in multi-ton quantities with degrees of substitution (DS) ranging from that of hydrolyzed, water-soluble monoacetates to those of fully substituted triacetate (Table 1). Soluble cellulose acetate was first prepared in 1865 by heating cotton and acetic anhydride at 180°C (1). Using sulfuric acid as a catalyst permitted preparation at lower temperatures (2), and later, partial hydrolysis of the triacetate gave an acetone-soluble cellulose acetate (3). The solubiUty of partially hydrolyzed (secondary) cellulose acetate in less expensive and less toxic solvents such as acetone aided substantially in its subsequent commercial development. 

Production of cellulose esters from aromatic acids has not been commercialized because of unfavorable economics. These esters are usually prepared from highly reactive regenerated cellulose, and their physical properties do not differ markedly from cellulose esters prepared from the more readily available aHphatic acids. Benzoate esters have been prepared from regenerated cellulose with benzoyl chloride in pyridine—nitrobenzene (27) or benzene (28). These benzoate esters are soluble in common organic solvents such as acetone or chloroform. Benzoate esters, as well as the nitrochloro-, and methoxy-substituted benzoates, have been prepared from cellulose with the appropriate aromatic acid and chloroacetic anhydride as the impelling agent and magnesium perchlorate as the catalyst (29). 

Reaction of HOCl, formed from calcium hypochlorite and CO2, with highly substituted alkenes in CH2CI2 is a convenient route to aHyUc chlorides (111). Ketones are chlorinated to a-chloroketones by reaction with HOCl Acetone initially gives CH2COCH2CI (112). Methyl ethyl ketone gives 78% CH3CHCICOCH3, 15% CH3CH2COCH2CI, and 7% dichlorides (113). 

Methyl chloride can be converted iato methyl iodide or bromide by refluxing ia acetone solution ia the presence of sodium iodide or bromide. The reactivity of methyl chloride and other aUphatic chlorides ia substitution reactions can often be iacteased by usiag a small amount of sodium or potassium iodide as ia the formation of methyl aryl ethers. Methyl chloride and potassium phthalimide do not readily react to give /V-methy1phtha1imide unless potassium iodide is added. The reaction to form methylceUulose and the Williamson synthesis to give methyl ethers are cataly2ed by small quantities of sodium or potassium iodide. 

Cocoa butter substitutes and equivalents differ greatly with respect to their method of manufacture, source of fats, and functionaHty they are produced by several physical and chemical processes (17,18). Cocoa butter substitutes are produced from lauric acid fats such as coconut, palm, and palm kernel oils by fractionation and hydrogenation from domestic fats such as soy, com, and cotton seed oils by selective hydrogenation or from palm kernel stearines by fractionation. Cocoa butter equivalents can be produced from palm kernel oil and other specialty fats such as shea and ilHpe by fractional crystallization from glycerol and selected fatty acids by direct chemical synthesis or from edible beef tallow by acetone crystallization. 

Hydroxyl Group. The OH group of cyanohydrins is subject to displacement with other electronegative groups. Cyanohydrins react with ammonia to yield amino nitriles. This is a step in the Strecker synthesis of amino acids. A one-step synthesis of a-amino acids involves treatment of cyanohydrins with ammonia and ammonium carbonate under pressure. Thus acetone cyanohydrin, when heated at 160°C with ammonia and ammonium carbonate for 6 h, gives a-aminoisobutyric acid [62-57-7] in 86% yield (7). Primary and secondary amines can also be used to displace the hydroxyl group to obtain A/-substituted and Ai,A/-disubstituted a-amino nitriles. The Strecker synthesis can also be appHed to aromatic ketones. Similarly, hydrazine reacts with two molecules of cyanohydrin to give the disubstituted hydrazine. 

These effects can be attributed mainly to the inductive nature of the chlorine atoms, which reduces the electron density at position 4 and increases polarization of the 3,4-double bond. The dual reactivity of the chloropteridines has been further confirmed by the preparation of new adducts and substitution products. The addition reaction competes successfully, in a preparative sense, with the substitution reaction, if the latter is slowed down by a low temperature and a non-polar solvent. Compounds (12) and (13) react with dry ammonia in benzene at 5 °C to yield the 3,4-adducts (IS), which were shown by IR spectroscopy to contain little or none of the corresponding substitution product. The adducts decompose slowly in air and almost instantaneously in water or ethanol to give the original chloropteridine and ammonia. Certain other amines behave similarly, forming adducts which can be stored for a few days at -20 °C. Treatment of (12) and (13) in acetone with hydrogen sulfide or toluene-a-thiol gives adducts of the same type. 

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