Alcoholysis and Phenolysis

It was reported that the reaction of starch with phenol in the presence of a Lewis acid such as AICI3 resulted in resins of controlled melt viscosity.252 Probably, the product results from the hydrolysis of starch to glucose with conbversion of the latter into 5-(hydroxymethyl)-2-furaldehyde, which subsequently condensed with phenol.253 The reaction of starch with phenol without any catalyst required temperatures between 200 and 260 °C, and the resultant resinous product was then hardened by condensation with formaldehyde.254 Mastication of either glycerol or phenol with starch and water was said not to involve alcoholysis, but instead results in the formation of polymeric products.255 Reactions with gossypol256,257 and propylene glycol258 that were performed in the presence of a basic catalyst were in fact polymerization reactions and not alcoholyses. 

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Direct hydrolysis of (monohalogenoalkyl)quinoxalines can be difficult but indirect routes are available. Alcoholysis and phenolysis are usually straightforward processes. The following examples illustrate both direct and indirect procedures. 

Reactions. Although both C-alkylsulfinyl- and C-alkylsulfonylquinoxalines have great potential as versatile intermediates, especially for displacement reactions, they have seldom been used as such in recent years for example, their hydrolysis, alcoholysis, and phenolysis have been totally ignored. However, an example of the conversion of an arylsulfonyl-into a halogenoquinoxaline has been given in Section 3.1.5, and some other reported reactions are illustrated in the following examples. 

Of these and related displacement reactions to produce phthalazines with oxygen-joined substituents, only alcoholysis and phenolysis have been used extensively. The following classified examples involve both nuclear and extra-... 

In a study on the example of model reactions of polycondensation of aroyl-bis-4-hydroxybenzoyl chlorides with aliphatic and aromatic dipoles, it was shown in [17] that the competing reactions of alcoholysis and phenolysis do not affect (in conditions identical to polycondensation) the internal aromatic ester bonds in the mesogenic fragment. In contrast to them, the tominal ester bonds in the fragment und go alcoholysis, but this does not result in perturbation of the regularity of the structure of the polyether. The interchain exchange reaction could be the cause of perturbation of the regularity of the structure of the chain, but NMR spectroscopy showed that the perturbations of the structure of the terephthaloyl-bis-4-hydroxybenzoate triad did not take place [17]. 

The same synthetic approach was used for the preparation of cyclic anhydrides [39- 3]. It was known before that succinic and glutaric acid form cyclic anhydrides which do not polymerize (see Formula 3.1, bottom). HiU and Carothers studied the reactions of higher dicarboxylic acids with acetyl chloride or acetic anhydride. In aU cases, polymeric anhydrides were obtained which were supposed to possess mixed anhydride end groups containing acetyl residues. The sensitivity to hydrolysis alcoholysis and phenolysis prevented exact molar mass measurements. However, a reliable distinction from monomeric cyclic anhydrides was achieved by reaction with aniline, because cyclic anhydrides can only yield one reaction product. When the polymeric anhydrides were heated to 150 °C in vacuum they degraded almost completely by back-biting . In this way 10 new cyclic anhydrides were isolated. These cyclic anhydrides underwent rapid polymerization in contact with traces of moisture. 

Most alkoxy- or aryloxyquinoxalines have been made by primary synthesis (see Chapter 1), by alcoholysis or phenolysis of halogenoquinoxalines (see Sections 3.2.2 and 3.4.2), or by 0-alkylation of tautomeric quinoxalinones or extranuclear hydroxyquinoxalines (see Sections 4.1.2.2 and 4.3.2). The remaining preparative routes are illustrated by the following classified examples. 

The reaction of a carboxylic acid with N,Af -carbonyldiimidazolellH33 (abbreviated as CDI), forming an imidazolide as the first step followed by alcoholysis or phenolysis of the imidazolide (second step), constitutes a synthesis of esters that differs from most other methods by virtue of its particularly mild reaction conditions.t41,[5] It may be conducted in two separate steps with isolation of the carboxylic acid imidazolide, but more frequently the synthesis is carried out as a one-pot reaction without isolation of the intermediate. Equimolar amounts of carboxylic acid, alcohol, and CDI are allowed to react in anhydrous tetrahydrofuran, benzene, trichloromethane, dichloromethane, dimethylformamide, or nitromethane to give the ester in high yield. The solvents should be anhydrous because of the moisture sensitivity of CDI (see Chapter 2). Even such unusual solvent as supercritical carbon dioxide at a pressure of 3000 psi and a temperature of 36-68 °C has been used for esterification with azolides.[6]... 

Reactions of alkylsulfinyl- and alkylsulfonylpyrazines also have limited representation in recent literature. Their alcoholysis or phenolysis is covered in Section 5.3.1 other reactions are illustrated in the following examples ... 

Note The formation of these ethers by primary synthesis Chapter 1), by alcoholysis or phenolysis of halogenocinnolines (Section 3.2), and by alkylation of tautomeric cinnolinones (Section 4.1.2.1) has been covered already. Other routes appear to be unrepresented. 

Such compounds are usually made by primary synthesis (see Chapter 8), by epoxidation of alkenylphthalazines (see Section 9.2.2), by alcoholysis or phenolysis of halogenophthalazines (see Section 10.3.3), by alkylation of tautomeric phtha-lazinones or extranuclear hydroxyphthalazines (see Sections 11.1.2 and 11.2.2), or by other routes that are illustrated in the following classified examples. 

Method of synthesis polyarylate Is the polyester derived from bisphenol-A and a mixture of Isophthallc and terephthalic acids by acidolysis, phenolysis, alcoholysis and esterolysis Han, X Padia, A B Hall, H K, J. Polym. Sci. A, 37,2891-97,1999. 

Note Alkoxy/aryloxy-l,8-naphthyridines have been made by primary synthesis (see Chapter 22), by alcoholysis/phenolysis of halogeno-l,8-naphthyridines (see Section 24.2), by alkylation of 1,8-naphthyridinones (see Section 25.1.2), and by two minor procedures illustrated here. 

The second method for liquefaction makes use of solvolysis during the process [8,11]. By using conditions which allow phenolysis of part of the lignin, especially in the presence of an appropriate catalyst, the liquefaction of chemically modified wood into phenols could be accomplished under milder conditions (at 80 C for 30-150 min). Allylated wood, methylated wood, ethylated wood, hydroxyethylated wood, acetylated wood, and others have been found to dissolve in polyhydric alcohols such as 1,6-hexanediol, 1,4-butanediol, 1,2-ethanediol, 1,2,3-propanetriol (glycerin), and bisphenol A using the liquefaction conditions just described. Each of them caused partial alcoholysis of lignin macromolecules [4]. 

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