Phenols with primary amines

The elaboration of routine synthetic methodologies such as the condensation reaction of 2-formyl- or 2-acyl-phenols with primary amines, sometimes followed by reduction, can be utilized in the synthesis of poly-aryloxide ligands including macro-cyclic examples. Some types of tris-aryloxides obtained in this way are shown in Scheme 6.7 (A) and Examples of a nonmacrocyclic tetra-aryloxide (C), and... 

This reaction can also be utili2ed to prepare functionali2ed initiators by reaction of butyUithium with a substituted 1,1-diphenylethylene derivative. For example, polymers end functionali2ed with primary amine, tertiary amine, phenol, and bis(phenol) groups have been prepared in essentiaUy quantitative yield by using the reaction of butyUithium with the corresponding substituted (or protected) 1,1-diphenylethylene (87). 

Thiophosgene reacts with alcohols and phenols to form chlorothionoformates or thiocarbonates. The most studied reactions of thiophosgene are with primary amines to give isothiocyanates and with secondary amines to give thiocarbamyl chlorides ... 

With phenols, thionyl chloride forms the aryl chlorides only in exceptional cases, eg, with ttinitrophenol (picric acid). The reaction of thionyl chloride with primary amines produces thionylamines. 

Vanillin reacts with primary amines in weakly basic media to form fluorescent or colored Schiff s bases whereby colored phenolates are also produced at the same time. 

Isothiocyanates react with nucleophiles such as amines, sulfhydryls, and the phenolate ion of tyrosine side chains (Podhradsky et al., 1979). The only stable product, however, is with primary amine groups, and so TRITC is almost entirely selective for modifying s- and N-terminal amines in proteins. The reaction involves attack of the nucleophile on the central, electrophilic... 

The reactions of the fused ring compound (5S) with secondary amines, giving (69) as a mixture of isomers and of (67) (X = Br) with t-butanol (and phenol) have been studied. With primary amines, cage compounds such as (68) are the major products Cage-forming reactions of this general type were first... 

Fluorogenic labelling of pesticides. The subject has been reviewed earlier by Lawrence and Frei (27). Labelling consists in replacing a proton or other atom of a pesticide with a so-called labelling compound such as dansyl chloride (V) or fluores-camine (VI). The former reacts with primary and secondary amines, phenols, some thiols and aliphatic alcohols. The latter reacts very selectively with primary amines. 

Reaction with primary amines proceeds differently from the 2,6-dialkyl-phenol case, generally stopping at the 1 1 adduct, XXIV. 

Ring formations by nucleophilic substitution at saturated carbon atoms with primary amines as nucleophiles have rarely been carried out because the resulting secondary amines as a rule are more nucleophilic than the primary ones, and therefore competition reactions are favored. The synthesis of secondary amines often starts from toluene sulfonamides which can easily be deprotonated and alkylated. A large number of methods for detosylation exists especially the acidic cleavage with H2SO4 or with HBr/phenol have proved to be reliable. 

Although formaldehyde has been most common, other aldehydes have also been used successfully for the formation of iminium ion. The Mannich reaction also proceeds with the other activated hydrogen compounds such as indole, furan, pyrrole and phenols. When primary amine is used, the Mannich base formed is a secondary amine and may undergo further condensation to yield tertiary amine. The Mannich base may eliminate an amine... 

The nitroazo-compounds obtained by combination of nitrodiazo-compounds with primary amines may be diazotised and combined with phenols resulting nitrodisazo-compounds on reduction yield amido-compounds, which, when again diazotised and combined with a phenol, yield tertiary azo-compounds, containing three azo-groups. 

The 2-phenoxy-l,3-thiazin-4-one (130) reacts with primary amines at C-2, but the adducts (131) so formed eliminate phenol, prior to the incorporation of another molar equivalent of the amine. The products (132) are also unstable, and ring open to give guanidines (133) (Scheme 23) <85ZC430>. 

The reactions of DFP with primary amines, phenols and alcohols have been reported Basic conditions are required and products are as expected from a simple nucleophilic substitution reaction. 

It is highly active when used in combination with primary amine or phenolic antioxidants. 

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