3- Hydroxy phenols, reaction with

Reactions with Alcohols, Phenols, and Other Hydroxy Compounds... 

The reaction with sodium sulfite or bisulfite (5,11) to yield sodium-P-sulfopropionamide [19298-89-6] (C3H7N04S-Na) is very useful since it can be used as a scavenger for acrylamide monomer. The reaction proceeds very rapidly even at room temperature, and the product has low toxicity. Reactions with phosphines and phosphine oxides have been studied (12), and the products are potentially useful because of thek fire retardant properties. Reactions with sulfide and dithiocarbamates proceed readily but have no appHcations (5). However, the reaction with mercaptide ions has been used for analytical purposes (13)). Water reacts with the amide group (5) to form hydrolysis products, and other hydroxy compounds, such as alcohols and phenols, react readily to form ether compounds. Primary aUphatic alcohols are the most reactive and the reactions are compHcated by partial hydrolysis of the amide groups by any water present. 

Coumarin can also be formed by the reaction of phenol with diketene (40). Similarly, diphenols can react with hydroxycarboxyUc acids or beta-ketoesters to give hydroxycoumaria derivatives. The reaction of resorciaol with malic acid produces umbeUiferone (7-hydroxycoumaria) and its reaction with ethyl acetoacetate gives beta-methylumbeUiferone (7-hydroxy-4-methylcoumaria). 

Ca.rhoxyla.tlon, This is the process of iatroduciag a carboxyUc acid group iato a phenol or naphthol by reaction with carbon dioxide under appropriate conditions of heat and pressure. Important examples are the carboxylation of phenol and 2-naphthol to give sahcyhc acid and 2-hydroxy-3-naphthoic acid, respectively. 

These compounds usually give many of the reactions characteristic of phenols and were long considered to exist completely in the hydroxy form (see, for example, reference 42). It has been noted that the ultraviolet spectra of aqueous ethanolic solutions of hydroxy-acridines varied with changes in the composition of the solvent, and this phenomenon has been interpreted in terms of the equilibria 132 133 and 134 135. Some compounds of these types show... 

The formylation of a phenol 1 with chloroform in alkaline solution is called the Reimer-Tiemann reaction. It leads preferentially to formation of an ortho-formylated phenol—e.g. salicylic aldehyde 2 —while with other formylation reactions, e.g. the Gattermann reaction, the corresponding /jara-formyl derivative is obtained as a major product. The Reimer-Tiemann reaction is mainly used for the synthesis of o-hydroxy aromatic aldehydes. 

Reaction with alcohols is general for diazo compounds, but it is most often performed with diazomethane to produce methyl ethers or with diazo ketones to produce ot-keto ethers, since these kinds of diazo compounds are most readily available. With diazomethane the method is expensive and requires great caution. It is used chiefly to methylate alcohols and phenols that are expensive or available in small amounts, since the conditions are mild and high yields are obtained. Hydroxy compounds react better as their acidity increases ordinary alcohols do not react at... 

Still unexplained are the reactions, with periodate, of hydroxy phenols and certain oxygenated aromatic compounds,1 as well as of some a-amino acids not containing the 2-hydroxyamine structure.8... 

Epichlorohydrin is reacted with a variety of hydroxy, carboxy, and amino compounds to form monomers with two or more epoxide groups, and these monomers are then used in the reaction with bisphenol A [Lohse, 1987]. Examples are the diglycidyl derivative of cyclohex-ane-l,2-dicarboxylic acid, the triglycidyl derivatives of p-aminophenol and cyanuric acid, and the polyglycidyl derivative of phenolic prepolymers. Epoxidized diolefins are also employed (Sec. 9-8). 

In the reaction with 2-hydroxy derivatives of benzaldehyde, acetophenone, and benzophenone, the phenol group adds to the l N bond, the carbon atom of the carbonyl group inserts into the P-NMe bond, and the phosphorus atom becomes oxidized to give (140) (Equation (15)) <96CB>. 

Methylcoumarins bearing hydroxy and other electron-donating groups can be synthesized from the corresponding phenols by reaction with ethyl acetoacetate in the presence of sulfuric acid. Hydrolysis of the ester group in the product then allows the lactone ring of the coumarin to form (Scheme 5.6). 

Examples where the phenolic hydroxy groups were utilized include the preparation of lignin epoxies by reaction with epichlorohydrin (2), esterifications with bis-acid chlorides (3) and cyanuric chloride (4), and polymerization with aziridines (5). 

The major functional groups in lignin are methoxy, phenolic hydroxy, aliphatic hydroxy, and carboxy groups. During reaction with alkylene oxide, most of the functional groups of lignin, besides methoxy groups, become... 

Heat resistant resin compositions based on BMI/aminophenol-Epoxy blends are achieved by reacting a BMI/p-aminophenol 1 1 adduct with epoxy resin (62). Both the secondary amine and phenol functionality may react with the epoxy resin and subsequently cure through an imidazole catalyst. Imidazole catalysts promote both the epoxy/phenol reaction and the anionic maleimide crosslinking. The formation of a 1 2 BMI/aminophenol adduct, as in Fig. 20, is claimed in a patent (63). The hydroxy terminated BMI/aminophenol adduct is an advantageous curing agent for epoxy resins when high temperature performance is desired. 

Both aromatic and aliphatic fluoroformates 7 can be readily prepared from phenols or alcohols and carbonyl difluoride and treated with sulfur tetrafluoride without isolation. Hydrogen fluoride evolved in the reaction of hydroxy compounds with carbonyl di fluoride serves as a catalyst for the consecutive reaction with sulfur tetrafluoride.15<)-162 This provides a general, convenient, direct synthesis of aryl and alkyl trifluoromethyl ethers 5 from phenols and alcohols. When the intermediate fluoroformate 7 is isolated prior to treatment with sulfur tetrafluoride, at least one mole equivalent of hydrogen fluoride is necessary to promote the fluorination reaction. 159 163 Representative examples of the conversion of hydroxy compounds 6 into trifluoromethyl ethers 5 via intermediate fluoroformates 7 are given (for other examples 7 -> 5, see Houben-Weyl, Vol. E4, pp 628. 629). 

However, chromones react differently, because the phenolic hydroxy group in the ring-opened intermediate is unreactive. Thus, isoxazoles (264) result from the reaction with hydroxylamine, and a pyrazole is formed with hydrazine. y-Pyrones also give pyrazoles with hydrazine. 

Reaction XXXVI. Condensation of Carbon Tetrachloride with Phenols and simultaneous Hydrolysis (Tiemann-Reimer). (B., 10, 2185.)—This reaction is closely analogous to that of the formation of hydroxy-aldehydes by means of chloroform and caustic alkali (see p. 104). A mixture of a phenol, carbon tetrachloride and caustic soda or caustic potash solution is boiled. Condensation occurs, chiefly in the para-position, but small amounts of the ortho-acids are also formed. The product, after the excess of carbon tetrachloride has been removed, is saturated with carbon dioxide and the unchanged phenol extracted with ether. The hydroxy acids are then precipitated by acidification with hydrochloric acid. 

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