Sulfonates nucleophilic-displacement reactions

Nucleophilic substitution reactions, to which the aromatic rings are activated by the presence of the carbonyl groups, are commonly used in the elaboration of the anthraquinone nucleus, particularly for the introduction of hydroxy and amino groups. Commonly these substitution reactions are catalysed by either boric acid or by transition metal ions. As an example, amino and hydroxy groups may be introduced into the anthraquinone system by nucleophilic displacement of sulfonic acid groups. Another example of an industrially useful nucleophilic substitution is the reaction of l-amino-4-bromoanthraquinone-2-sulfonic acid (bromamine acid) (76) with aromatic amines, as shown in Scheme 4.5, to give a series of useful water-soluble blue dyes. The displacement of bromine in these reactions is catalysed markedly by the presence of copper(n) ions. 

Bimolecular, nucleophilic-displacement reactions of sugar sulfonates have been reviewed in this Series.58,59 The value of these reactions in the preparation of deoxyhalo sugars has been emphasized by Hanessian.92... 

Azidodeoxy sugars are useful intermediates in the synthesis of aminodeoxy sugars. Nucleophilic-displacement reactions of sulfonate and deoxyhalo derivatives of sucrose with sodium azide have been used for the preparation of sucrose azides. The reaction of... 

Sulfides in the electrophilic positions are often oxidized to sulfones to facilitate nucleophilic displacement reactions. The sulfoxide is initially formed, and can sometimes be isolated, but normally the oxidation is allowed to proceed fully to give the sulfone. Peroxyacids are commonly used as the oxidant, although other reagents such as oxone (potassium peroxymonosulfate) can also be employed <20030L1011, 2006ARK(vii)452>. 

Bimolecular, nucleophilic-displacement reactions of sulfonic esters of carbohydrates have been reviewed.77,78... 

Nucleophilic Displacement Reactions of lmidazole-1-Sulfonate Esters... 

J. M. Sugihara and W. J. Teerlink, Stereochemical effects in the nucleophilic displacement reactions of primary carbohydrate benzene sulfonate esters with sodium iodide, J. Org. Chem. 29 550 (1964). 

In a solution of sodium sulfite at pH 5, thiamin is cleaved by what appears to be a nucleophilic displacement reaction on the methylene group to give the free thiazole and a sulfonic acid. 

Figure 15.8 Arylsulfonate resins and their cleavage by imidazole, thiolates and primary and secondary amines. The sulfonate resin acts as the leaving group in the nucleophilic displacement reaction.

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