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Alcohols Phenol

Reactions with Alcohols, Mercaptans, and Phenols. Alcohols add readily to acetaldehyde in the presence of trace quantities of mineral acid to form acetals eg, ethanol and acetaldehyde form diethyl acetal [105-57-7] (65). Similarly, cycHc acetals are formed by reactions with glycols and other polyhydroxy compounds eg, ethylene glycol [107-21-1] and acetaldehyde give 2-methyl-1,3-dioxolane [497-26-7] (66) ... [Pg.50]

In this case the formation of phenol-alcohols is rapid but their subsequent condensation is slow. Thus there is a tendency for polyalcohols, as well as monoalcohols, to be formed. The resulting polynuclear polyalcohols are of low molecular weight. Liquid resols have an average of less than two benzene rings per molecule, while a solid resol may have only three to four. A typical resol would have the structure shown in Figure 23.12. [Pg.641]

The reaction mixture is heated and allowed to reflux, under atmospheric pressure at about 100°C. At this stage valve A is open and valve B is closed. Because the reaction is strongly exothermic initially it may be necessary to use cooling water in the jacket at this stage. The condensation reaction will take a number of hours, e.g. 2-4 hours, since under the acidic conditions the formation of phenol-alcohols is rather slow. When the resin separates from the aqueous phase and the resin reaches the requisite degree of condensation, as indicated by refractive index measurements, the valves are changed over (i.e. valve A is closed and valve B opened) and water present is distilled off. [Pg.644]

In the manufacture of resols a molar excess of formaldehyde (1.5-2.0 1) is reacted with the phenol in alkaline conditions. In these conditions the formation of the phenol alcohols is quite rapid and the condensation to a resol may take less than an hour. A typical charge for a laboratory-scale preparation would be ... [Pg.645]

Amongst the catalysts used or the polymerisation-trimerisation reactions are alkali metal phenolates, alcoholates and carboxylates and compounds containing o-(dimethylaminomethyl)phenol subgroups. Fluorocarbons such as trichloro-fluoromethanes are used as the sole blowing agents in the absence of any isocyanate-water reaction. [Pg.806]

Resoles are usually those phenolics made under alkaline conditions with an excess of aldehyde. The name denotes a phenol alcohol, which is the dominant species in most resoles. The most common catalyst is sodium hydroxide, though lithium, potassium, magnesium, calcium, strontium, and barium hydroxides or oxides are also frequently used. Amine catalysis is also common. Occasionally, a Lewis acid salt, such as zinc acetate or tin chloride will be used to achieve some special property. Due to inclusion of excess aldehyde, resoles are capable of curing without addition of methylene donors. Although cure accelerators are available, it is common to cure resoles by application of heat alone. [Pg.874]

The second phase in resole formation is reaction of the activated phenol with the aldehyde to form the phenol alcohol derivative. When the aldehyde is formaldehyde, the derivative is a hydroxymethyl phenol and the process is known as methylolation. Scheme 2 illustrates this reaction. Since resoles are usually made with excess aldehyde, more than one substitution may be made on the ring. When the reactants are phenol and formaldehyde, up to three methylol groups may be substituted. This reaction has been extensively studied and the rates of... [Pg.883]

The general definition of a condensation reaction is a one that involves product formation by expulsion of water (or other small molecule) as a by-product. By this definition, activation and methylolation are also condensations. In more precise terms the chain-building process should be described as a condensation polymerization, however, in the jargon of the phenolics industry, the term condensation is usually reserved for the chain-building process. This terminology is not necessarily observed in the literature [88]. Many literature reports correctly refer to methylolation as a condensation reaction. The molecular weight development of the phenol alcohol adducts may also be classified as a step-polymerization. [Pg.887]

Group of plastics composed of resins produced by reactions of epoxides or oxiranes with compounds such as amines, phenols, alcohols, carboxylic acids, acid anhydrides and unsaturated compounds. [Pg.132]

Mono-substitution occurs most readily in the stepwise replacement of the halogen substituents of 2,4,6-trichloro-s-triazine with aqueous methanol and sodium bicarbonate (30°, 30 min), the monomethoxy derivative (324) is obtained on heating (65°, 30 min), the disubstitu-ted derivative is formed and on brief heating (65°) with the more basic sodium carbonate or methanolic sodium hydroxide (25°, 3 hr) complete methoxylation (320) occurs. Ethanolic ethoxide (25°, 1 hr) or sodium carbonate (35°) is sufficient to give complete ethoxy-dechlorination. The corresponding phenoxy derivatives are obtained on treatment with one (0°), two (15°, 1 hr), or three equivalents (25-70°, 3 hr) of various sodium phenoxides in aqueous acetone. The stepwise reaction with phenols, alcohols, or thiols proceeds in better yield in organic solvents (acetone or chloroform) with collidine or 2,6-lutidine as acid acceptors than in aqueous sodium bicarbonate. ... [Pg.302]

Viruses that contain hpid are inactivated by organic solvents such as chloroform and ether. Those without hpid are resistant to these agents. This distinction has been used to classify virases. Many of the chemical disinfectants used against bacteria, e.g. phenols, alcohols and quaternary ammonium compounds (Chapter 10), have minimal virucidal activity. The most generally active agents are chlorine, the hypochlorites, iodine, aldehydes and ethylene oxide. [Pg.57]

Extractive alkylation is used to derivatize acids, phenols, alcohols or amides in aqueous solution [435,441,448,502]. The pH of the aqueous phase is adjusted to ensure complete ionization of the acidic substance which is then extracted as an ion pair with a tetraalkylammonium hydroxide into a suitable immiscible organic solvent. In the poorly solvating organic medium, the substrate anion possesses high reactivity and the nucleophilic displacement reaction with an alkyl halide occurs under favorable conditions. [Pg.945]

The same laboratory has prepared three tridentate zinc chelates from chiral tertiary amino phenolic alcohols and used them for enantioselective addition of diethylzinc to aryl aldehydes in 70-87% ee. Results with the ligand 4 [from (1S,2S)-(+ )-pseudoephedrine] are typical. [Pg.160]

The ability of quaternary ammonium halides to form weakly H-bonded complex ion-pairs with acids is well established, as illustrated by the stability of quaternary ammonium hydrogen difluoride and dihydrogen trifluorides [e.g. 60] and the extractability of halogen acids [61]. It has also been shown that weaker acids, such as hypochlorous acid, carboxylic acids, phenols, alcohols and hydrogen peroxide [61-64] also form complex ion-pairs. Such ion-pairs can often be beneficial in phase-transfer reactions, but the lipophilic nature of H-bonded complex ion-pairs with oxy acids, e.g. [Q+X HOAr] or [Q+X HO.CO.R], inhibits O-alkylation reactions necessitating the maintenance of the aqueous phase at pH > 7.0 with sodium or potassium carbonate to ensure effective formation of ethers or esterification [49,64]. [Pg.14]

Synonyms AI3-01814 AIDS-352 Baker s P and S liquid and ointment Benzenol BRN 0969616 Carbolic acid Carbolic oil Caswell No. 649 CCRIS 504 CRS EINECS 203-632-7 EPA pesticide chemical code 064001 FEMA No. 3223 Fenosmolin Fenosmoline Hydroxy-benzene IPH Izal Monohydroxybenzene Monophenol NA 2821 NCI-C50124 NSC 36808 Oxybenzene Phenic acid Phenic alcohol Phenol alcohol Phenyl hydrate Phenyl hydroxide Phenylic acid Phenylic alcohol RCRA waste number U188 UN 1671 UN 2312 UN 2821. [Pg.949]

Lignins are high polymers of phenolic alcohols such as coniferyl alcohol (Fig. 11.2). They increase the toughness of the plant and form wood, obviously useful for defense against herbivores. [Pg.274]

This set of enzymes [EC 2.4.1.17], also known as UDP-glucuronosyltransferases, catalyzes the reaction of UDP-glucuronate with an acceptor to produce UDP and the 13-D-glucuronoside of the acceptor. This family of proteins accepts a wide range of substrates, including phenols, alcohols, amines, and fatty acids. [Pg.314]

Phenolic alcohols 3,4-Dihydroxyphenyhethanol (3,4-DHPEA) OR / -Hydroxyphenyhethanol (/ -HPEA) HO - (3,4-Dihydroxyphenyl)ethanol-glucoside 2-(4-Hydroxyphenyl)ethylacetate ... [Pg.599]

In the 1990s, the groups of Hiemstra and Larock independently discovered that Pd(OAc)2 in DMSO serves as an effective catalyst for direct dioxygen-coupled catalytic turnover, and this catalyst system was applied widely to oxidative heterocyclization reactions. Examples include the addition of carboxylic acid, phenol, alcohol, formamide, and sulfonamide nucleophiles to pendant olefins (Eq. 26) [146-149]. [Pg.96]


See other pages where Alcohols Phenol is mentioned: [Pg.404]    [Pg.269]    [Pg.132]    [Pg.907]    [Pg.322]    [Pg.839]    [Pg.208]    [Pg.943]    [Pg.440]    [Pg.120]    [Pg.131]    [Pg.223]    [Pg.74]    [Pg.103]    [Pg.101]    [Pg.442]    [Pg.124]    [Pg.169]    [Pg.196]    [Pg.1504]    [Pg.91]    [Pg.20]    [Pg.544]    [Pg.598]    [Pg.123]    [Pg.432]   
See also in sourсe #XX -- [ Pg.40 ]

See also in sourсe #XX -- [ Pg.40 ]

See also in sourсe #XX -- [ Pg.40 ]




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A Comparison of Alcohols and Phenols

ALCOHOLS, ETHERS, THIOLS AND PHENOLS

ALCOHOLS, PHENOLS, ETHERS, THIOLS, AND THIOETHERS

ALKYLATION OF ALCOHOLS AND PHENOLS

Acidity alcohols and phenols

Acidity of Alcohols and Phenols

Acylation of alcohols and phenols

Addition of alcohols and phenols

Alcohol with phenol peels

Alcoholic and Phenolic Groups

Alcohols and Phenols ROH, ArOH

Alcohols and phenols

Alcohols phenols, synthesis

Alcohols, Enols, and Phenols

Alcohols, Phenols and Carboxylic Acids as Asymmetric Organocatalysts

Alcohols, Phenols and Ethers

Alcohols, Phenols, Ethers, and Thioalcohols

Alcohols, Phenols, and Carboxylic Acids

Alcohols, Phenols, and Thiols

Alcohols, phenols and their derivatives

Alcohols, phenols names

Alkali Metal Alcoholate and Phenolate Active Sites

Amine, Phenol, Alcohol, and Thiol Arylation

Aromatic Alcohols, Phenols, and Ethers

Arylation of Phenols, Alcohols, and Thiols

Benzyl alcohol, separation from phenol

Bonding in alcohols and phenols

Deprotection alcohol/phenol groups

Derivatives of Alcohols and Phenols

Diazomethane reaction with alcohols and phenols

Dithioesters alcohols and phenols

Electrophilic Addition of Alcohols and Phenols

Elimination Reactions of Alcohols, Enols, and Phenols

Fragmentation Patterns of Alcohols, Phenols, and Thiols

Gas phase acidity of alcohols and phenols

Halides from Alcohols and Phenols by Triphenylphosphine Dihalide

Hydrogen Bonding in Alcohols and Phenols

Hydroxyl groups (alcohols and phenols)

Intermolecular reactions alcohols/phenols

Linkers for Alcohols and Phenols

Linkers for the Attachment of Alcohols or Phenols

Methylol derivatives Phenol alcohols

Naming Alcohols and Phenols

Naming Alcohols, Phenols, and Thiols

Nitrate Test for Alcohols and Phenols

Nomenclature of Alcohols and Phenols

Of alcohols and phenols

Oxidation of Alcohols and Phenols

Oxidation of Alcohols, Enols, and Phenols

Oxidation, alcohols phenols

Phenol Alcohols and their Esters

Phenol alcohol oligomers

Phenol benzyl alcohol, reactivity with

Phenol benzyl alcohol, reactivity with phenyl isocyanate

Phenol furfuryl alcohol

Phenol/hydroxybenzyl alcohol ratio

Phenolic alcohol components of lignin

Phenolic alcohols

Phenolic alcohols

Phenols alcohol chemistry

Phenols and aliphatic alcohols

Phenols distinguishing/separating from alcohols

Properties of Alcohols and Phenols

Properties of Alcohols and Phenols Hydrogen Bonding

Properties of Alcohols, Phenols, and Thiols

Protecting groups for alcohols and phenols

Reaction CV.—Action of Acid Anhydrides on Alcohols and Phenols

Reaction of Phenols and Benzyl Alcohols

Reaction with Alcohols, Phenol and Amines

Reactions of White Phosphorus with Alcohols and Phenols

Reactions with Alcohols and Phenols

Rearrangement Reactions of Alcohols, Enols, and Phenols

Reduction of Alcohols, Enols, and Phenols

Retained Trivial Names of Alcohols and Phenols with Structures

Rhodium-Catalyzed Allylic Etherifications with Phenols and Alcohols

Selective Deprotection of Alcoholic and Phenolic TBDMS Ethers

Spectroscopy of Alcohols and Phenols

Spectroscopy of Alcohols, Phenols, and Ethers

Substitution Reactions of Alcohol, Enols, and Phenols

Substitution Reactions of Alcohols, Enols, and Phenols at Oxygen

Telomerization of Butadiene with Alcohols and Phenol

The Acidity of Alcohols and Phenols

The Action of Boiling Alcohols and Dehydrated Phenols on Aluminium

The Basicity of Alcohols and Phenols

The Nomenclature of Alcohols and Phenols

Thioacylation alcohols and phenols

Thiols, the Sulfur Analogs of Alcohols and Phenols

Thioxoesters synthesis from alcohols and phenols

Thioxolactones synthesis from alcohols and phenols

Transformations with Alcohols and Phenols

With Water, Alcohols, and Phenols

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