Hydroxyalkylation, with sulfonic esters

Sulfinate esters (18) are isomeric with sulfones, but have very different properties. Cyclic sulfinate esters (sultines) (21) can be conveniently prepared by the action of sulfuryl chloride on t-2 butyl hydroxyalkyl sulfoxides (20) (Scheme 13). The most common reaction of sulfinate esters is nucleophilic substitution at sulfur with consequent sulfur-oxygen bond cleavage (Scheme 13). 

Esters. Most acryhc acid is used in the form of its methyl, ethyl, and butyl esters. Specialty monomeric esters with a hydroxyl, amino, or other functional group are used to provide adhesion, latent cross-linking capabihty, or different solubihty characteristics. The principal routes to esters are direct esterification with alcohols in the presence of a strong acid catalyst such as sulfuric acid, a soluble sulfonic acid, or sulfonic acid resins addition to alkylene oxides to give hydroxyalkyl acryhc esters and addition to the double bond of olefins in the presence of strong acid catalyst (19,20) to give ethyl or secondary alkyl acrylates. 

The resistance of the furoxan ring to chemical attack allows derivatives to be prepared via the reactions of the substituents (Section 4.22.3.4). Carboxylic acids are available by permanganate oxidation of methyl derivatives or by hydrolysis of the corresponding esters reaction with ammonia affords carboxamides. Acylfuroxans provide a source of hydroxyalkyl compounds by reduction, and oximes, for example, via nucleophilic addition. Acylation and oxidation of aminofuroxans allows the amide and nitro derivatives to be prepared. Nucleophilic displacements of nitro substituents can take place, but can be somewhat hazardous on account of the explosive nature of these compounds. Alkoxy derivatives are formed with sodium alkoxide, while reaction with thiolate anions yields sulfides, from which sulfones can be synthesized by peracid oxidation. Nitrofuroxans have also been reduced to... 

Polypyrrole (PPy) S alkyl S alkoxy S hydroxyalkyl S carboxyalkyl S alkyl sulfonic acid S amine S ester group G to PVA C with thiophene... 

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