Lederer-Manasse

The diarylation reaction is especicdly common with phenols (the diaryl product here is called a bisphenol). The reaction is normally carried out in alkaline solution on the phenolate ion. The hydroxymethylation of phenols with formaldehyde is called the Lederer-Manasse reaction. This reaction must be carefully controlled, since it is possible for the para and both ortho positions to be substituted and for each of... 

Condensations with carbonyl compounds phenol-formaldehyde resins. Acid or base catalyzes electrophilic substitution of carbonyl compounds in ortho and para positions of phenols to form phenol alcohols (Lederer-Manasse reaction). 

Reaction vtit. Condensation of a Phenol with Formaldehyde (Lederer-Manasse). (B., 27, 2411.)—This reaction can take three different courses according to conditions. 

Reaction XXXIH. (a) Condensation of an Aromatic Carboxylic Acid with Formaldehyde. (Lederer-Manasse).—In the presence of mineral acids formaldehyde condenses to di-phenyl derivatives with aromatic acids in much the same way as with phenols (Reaction XIII.), except that in this case it is in the meta position the condensation takes place. 

A). Introduction of hydroxymethyl groups into position ortho to the phenolate groups—i. e., reaction with the activated free S-positions of phenolic nuclei (Lederer-Manasse reaction) is expected to be the main reaction in alkali. 

Lederer-Manasse reaction, 439 Levorotation, 70 Lewis acids and bases, 44 Lewis structural formulas, 2 Ligands, 71 Lindlar s catalyst, 145... 

Resol-producing reaction mechanism (Lederer-Manasser s reaction)... 

Baekeland (Bakelite) process. Condensation of phenol and formaldehyde to o-hydroxyme-thylphenol (Lederer-Manasse), which undergoes further arylation yielding a polymeric stmcture. 

In aqueous alkaline solution, phenol reacts with formaldehyde (methanal) at low temperatures to form a mixture of 2- and 4-hydroxy-benzyl alcohols. This Lederer-Manasse reaction is another example of electrophilic attack which results in the formation of a new C-C bond. The mechanism is illustrated in Scheme 4.14. These products readily lose water to form quinomethanes (methylenecyclohexadienones), which react with more phenoxide. This process is repeated over and over again to produce a cross-linked polymer or phenol-formaldehyde resin (e.g. Bakelite) in which the aromatic rings are linked to methylene bridges. 

This reaction is related to the Baekeland-Lederer-Manasse Reaction, which gives resinous product from the reaction between phenol and formaldehyde. In addition, this reaction is related to Zinke Synthesis. 

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