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Anhydrides reaction with alcohols

Since amines react more readily than alcohols in noncatalyzed reactions with anhydrides, the reaction is more difficult and initially required stoichiometric catalyst loadings [107], but could be performed in a catalytic sense with an O-acylated azlactone as acylating agent, which does not react with a benzylic amine at —50°C, but is capable of acylating the catalyst [108, 109]. Depending on the buUdness of the substrate, selectivities ranged from S = 11 to 27 (s = [ enantiomer l]/[ enantiomer 2])-... [Pg.168]

Reactions with anhydrides and acid chlorides are more rapid and can occur in an essentially nonreversible fashion. But, anhydrides and acid chlorides are considered high-energy reactants since they often involve additional energy-requiring steps in their production, and are thus less suitable for large-scale production of materials. The activity energies for direct esterification and transesterification are on the order of 30 kcal/mol (120 kJ/mol) while the activation energies for anhydride and acid chloride reaction with alcohols are on the order of 15-20 kcal/mol (60-80 kJ/mol). [Pg.96]

It should finally be pointed out that trimethylsilyl ethers can also be transformed directly into other functionalities. Oxidation with NBS leads to ketones and aldehydes, treatment with LiAllWAlCb results in deoxygenation of the alcohol, reaction with carboxylic acid anhydrides in the presence of BF3-OEt2 produces esters and on treatment with PhsP Brj acid bromides are foimed directly from TMS esters. ss... [Pg.655]

A variety of reactions are available for the preparation of alkoxyacetoxysilane species. Among them are the reactions of tetra-acetoxysilane with alcohols , tetraalkoxysilanes with anhydrides of alkoxychlorosilanes with acetate salts, and of hydrosilanes with anhydrides as exemplified by... [Pg.340]

The alcohol groups of carbohydrates undergo chemical reactions typical of hydroxyl functions They are converted to esters by reaction with acyl chlorides and carboxylic acid anhydrides... [Pg.1058]

Acetals are readily formed with alcohols and cycHc acetals with 1,2 and 1,3-diols (19). Furfural reacts with poly(vinyl alcohol) under acid catalysis to effect acetalization of the hydroxyl groups (20,21). Reaction with acetic anhydride under appropriate conditions gives the acylal, furfuryUdene diacetate... [Pg.77]

The primary and secondary alcohol functionahties have different reactivities, as exemplified by the slower reaction rate for secondary hydroxyls in the formation of esters from acids and alcohols (8). 1,2-Propylene glycol undergoes most of the typical alcohol reactions, such as reaction with a free acid, acyl hahde, or acid anhydride to form an ester reaction with alkaU metal hydroxide to form metal salts and reaction with aldehydes or ketones to form acetals and ketals (9,10). The most important commercial appHcation of propylene glycol is in the manufacture of polyesters by reaction with a dibasic or polybasic acid. [Pg.366]

Commodity Phthalate Esters. The family of phthalate esters are by far the most abundandy produced woddwide. Both orthophthaUc and terephthahc acid and anhydrides are manufactured. The plasticizer esters are produced from these materials by reaction with an appropriate alcohol (eq. 1) terephthalate esterification for plasticizers is performed more abundandy in the United States. Phthalate esters are manufactured from methanol (C ) up to Qyj alcohols, although phthalate use as PVC plasticizers is generally in the range to The lower molecular weight phthalates find use in nitrocellulose the higher phthalates as synthetic lubricants for the automotive industries. [Pg.122]

Ahyl alcohol undergoes reactions typical of saturated, aUphatic alcohols. Ahyl compounds derived from ahyl alcohol and used industriahy, are widely manufactured by these reactions. For example, reactions of ahyl alcohol with acid anhydrides, esters, and acid chlorides yield ahyl esters, such as diahyl phthalates and ahyl methacrylate reaction with chloroformate yields carbonates, such as diethylene glycol bis(ahyl carbonate) addition of ahyl alcohol to epoxy groups yields products used to produce ahyl glycidyl ether (33,34). [Pg.74]

The Prins reaction with formaldehyde, acetic acid, acetic anhydride, and camphene gives the useful alcohol, 8-acetoxymethyl camphene, which has a patchouli-like odor (83). Oxidation of the alcohol to the corresponding aldehyde also gives a useful iatermediate compound, which is used to synthesize the sandalwood compound dihydo- P-santalol. [Pg.416]

The other analytical methods necessary to control the typical specification given in Table 5 are, for the most part, common quality-control procedures. When a chemical analysis for purity is desired, acetylation or phthalation procedures are commonly employed. In these cases, the alcohol reacts with a measured volume of either acetic or phthalic anhydride in pyridine solution. The loss in titratable acidity in the anhydride solution is a direct measure of the hydroxyl groups reacting in the sample. These procedures are generally free from interference by other functional groups, but both are affected adversely by the presence of excessive water, as this depletes the anhydride reagent strength to a level below that necessary to ensure complete reaction with the alcohol. Both procedures can be adapted to a semimicro- or even microscale deterrnination. [Pg.413]

Hydroboration affords an efficient preparation of the 5a-A -system (141, for example) from A" -3-ketones. Reaction with diborane followed by decomposition of the organoboron intermediate with refluxing acetic anhydride gives good yields of olefins. Ketones must be protected, and alcohols are transformed to acetates. A -7-Ketones yield 5oc-A -olefins (for example, 138). [Pg.347]

Reaction with alcohols (Section 15.8) Acid anhydrides react with alcohols to form esters. [Pg.843]

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]

The most important group of derivatives for the amino function (Fig. 7-4) is the carbamate group, which can be formed by reactions with acids, acid chlorides or acid anhydrides. A series of chlorides as 2-chloroisovalerylchloride [1], chrysanthe-moylchloride [2] and especially chloride compounds of terpene derivatives (cam-phanic acid chloride [3], camphor-10-sulfonyl chloride [4]) are used. The a-methoxy-a-trifluoromethylphenylacetic acid or the corresponding acid chloride introduced by Mosher in the 1970s are very useful reagents for the derivatization of amines and alcohols [5]. [Pg.188]

Phthalic anhydride s main use is for producing plasticizers by reactions with C4-C10 alcohols. The most important polyvinyl chloride plasticizer is formed by the reaction of 2-ethylhexanol (produced via butyraldehyde. Chapter 8) and phthalic anhydride ... [Pg.297]

Acid halides are among the most reactive of carboxylic acid derivatives and can be converted into many other kinds of compounds by nucleophilic acyl substitution mechanisms. The halogen can be replaced by -OH to yield an acid, by —OCOR to yield an anhydride, by -OR to yield an ester, or by -NH2 to yield an amide. In addition, the reduction of an acid halide yields a primary alcohol, and reaction with a Grignard reagent yields a tertiary alcohol. Although the reactions we ll be discussing in this section are illustrated only for acid chlorides, similar processes take place with other acid halides. [Pg.800]

Acetic anhydride, electrostatic potential map of, 791 reaction with alcohols, 807 reaction with amines, 807 reaction with monosaccharides, 988... [Pg.1281]

Phosphine(s), chirality of, 314 Phosphite, DNA synthesis and, 1115 oxidation of, 1116 Phospholipid, 1066-1067 classification of, 1066 Phosphopantetheine, coenzyme A from. 817 structure of, 1127 Phosphoramidite, DNA synthesis and, 1115 Phosphoranc, 720 Phosphoric acid, pKa of, 51 Phosphoric acid anhydride, 1127 Phosphorus, hybridization of, 20 Phosphorus oxychloride, alcohol dehydration with. 620-622 Phosphorus tribromide, reaction with alcohols. 344. 618 Photochemical reaction, 1181 Photolithography, 505-506 resists for, 505-506 Photon, 419 energy- of. 420 Photosynthesis, 973-974 Phthalic acid, structure of, 753 Phthalimide, Gabriel amine synthesis and, 929... [Pg.1311]

Acid anhydride-diol reaction, 65 Acid anhydride-epoxy reaction, 85 Acid binders, 155, 157 Acid catalysis, of PET, 548-549 Acid-catalyzed hydrolysis of nylon-6, 567-568 of nylon-6,6, 568 Acid chloride, poly(p-benzamide) synthesis from, 188-189 Acid chloride-alcohol reaction, 75-77 Acid chloride-alkali metal diphenol salt interfacial reactions, 77 Acid chloride polymerization, of polyamides, 155-157 Acid chloride-terminated polyesters, reaction with hydroxy-terminated polyethers, 89 Acid-etch tests, 245 Acid number, 94 Acidolysis, 74 of nylon-6,6, 568... [Pg.575]

The addition of acetic acid anhydride or acetyl chloride was found to accelerate the reaction. In certain instances other solvents are also used. Phosphates of higher molecular weight alcohols was formed by reaction with P4O10 or POCl3 in the presence of benzene [18-20]. Specific examples describe the reaction of P4O10 with diglycerides from vegetable oil in the presence of isopro-... [Pg.557]


See other pages where Anhydrides reaction with alcohols is mentioned: [Pg.253]    [Pg.903]    [Pg.3]    [Pg.232]    [Pg.380]    [Pg.332]    [Pg.50]    [Pg.52]    [Pg.283]    [Pg.336]    [Pg.218]    [Pg.450]    [Pg.1030]    [Pg.95]    [Pg.12]    [Pg.1128]    [Pg.1551]   
See also in sourсe #XX -- [ Pg.483 ]




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Acetic anhydride, electrostatic reaction with alcohols

Acid anhydride, amides from reaction with alcohols

Alcohol reaction with acid anhydrides

Anhydride benzoic, reaction with alcohols

Anhydrides cyclic, reaction with alcohols

Anhydrides reactions

Ethanol acid anhydride reaction with alcohol

Reaction with alcohols

Reaction with anhydrides

Triflic anhydride reaction with alcohols

With anhydrides

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