Sulfonic acid esters synthesis

Imidazolides of aromatic sulfonic acids react much more slowly in alcoholysis reactions than the carboxylic acid imidazolides. Although the reaction with phenols is quantitative when a melt is heated to 100 °C for several hours, with alcohols under these conditions only very slight alcoholysis is observed. In the presence of 0.05 equivalents (catalytic amount) of sodium ethoxide, imidazole sodium, of NaNH2, however, imidazolides of sulfonic acids react with alcohols almost quantitatively and exothermically at room temperature in a very short time to form sulfonic acid esters (sulfonates). (If the ratio of sulfonic acid imidazolide to alcoholate is 1 2, ethers are formed see Chapter 17). The mechanism of catalysis by base corresponds to that operative in the synthesis of carboxylic esters by the imidazolide method. Because of the more pronounced nucleophilic character of alkoxide ions, sulfonates can also be prepared in good yield by alcoholysis of their imidazolides in the presence of hydroxide ions i.e., with alcoholic sodium hydroxide. 45 Examples of syntheses of sulfonates are presented below. 

In 1967, Corey defined synthons as structural units within a molecule which are related to possible synthetic operations1. In organic synthesis, synthetic operations denote structural transformations of the molecule. This chapter deals with a number of very important synthetic operations, namely carbon-carbon bond formation and functional group transformations utilizing sulfonic acids, esters and their derivatives as synthons2. 

Adipic acid Butyl alcohol N-Hydroxysuccinic acid Isoborneol Isostearic acid PEG-6 acrylate PEG-9 acrylate Perchloric acid Succinic anhydride Xylene sulfonic acid ester mfg., flavoring n-Butyric acid ester mfg., flavoring agents Isobutyric acid Phenylacetyl chloride ester mfg., fragrances n-Butyric acid ester mfg., perfume bases Isobutyric acid ester mfg., plasticizers PPG-2 methyl ether ester mfg., solvents Isobutyric acid ester modifier Dimethyloctanyl acetate ester oil mfg., complex Isooctanoic acid ester synthesis Isocetyl alcohol... 

Synthesis of Precision Phosphonic Acid and Sulfonic Acid Ester-Functionalized Polyolefins... 

Sulfonic acid esters are more versatile than carboxylic acid esters due to their stability toward acids and bases and the way they are cleaved. Cleavage of carboxylic acid esters occurs by carbonyl-oxygen fission (reaction 4.11), while cleavage of sulfonic acid esters occurs by alkyl-oxygen fission (reaction 4.12). This latter chemical property makes them very useful in the synthesis of many carbohydrate derivatives and analogues in which the nucleophile is substituted onto the carbon atom of the carbohydrate. 

Other Applications. Hydroxylamine-O-sulfonic acid [2950-43-8] h.2is many applications in the area of organic synthesis. The use of this material for organic transformations has been thoroughly reviewed (125,126). The preparation of the acid involves the reaction of hydroxjlamine [5470-11-1] with oleum in the presence of ammonium sulfate [7783-20-2] (127). The acid has found appHcation in the preparation of hydra2ines from amines, aUphatic amines from activated methylene compounds, aromatic amines from activated aromatic compounds, amides from esters, and oximes. It is also an important reagent in reductive deamination and specialty nitrile production. 

In ref. [123], 1-triisopropylbenzenesulfonyl- or mesitylenesulfonyl-5-(pyridine-2-yl)-tetrazole (VIII) was successfully used as a coupling agent for the synthesis of protected di- and trinucleotides. In comparison with the sulfonic acid tetrazolides these are able to achieve a stereoselective synthesis of dinucleoside monophosphate aryl esters. 311 1241... 

Since PTFE was first synthesized more than 50 years ago, fluoropolymers have been produced by radical polymerization and copolymerizaton processes, but without any functional groups, for several reasons. First, the synthesis of functional vinyl compounds suitable for radical polymerization is much more complicated and expensive in comparison with common fluoroolefins. In radical polymerization of one of the simplest possible candidates—perfluorovinyl sulfonic acid (or sulfonyl fluoride—there was not enough reactivity to provide high-molecular-weight polymers or even perfluorinated copolymers with considerable functional comonomer content. Several methods for the synthesis of the other simplest monomer—trifluoroacrylic acid or its esters—were reported,1 but convenient improved synthesis of these compounds as well as radical copolymerization with TFE induced by y-irradiation were not described until 1980.2... 

Sulfonylhydroxylamines and hydroxylamine O-sulfonic acid have found wide apph-cation in synthesis of amines from achiral or chiral organoboranes and boronate esters and the hydroboration-amination methodology is successfully used for direct amination of alkenes. 0-Sulfonyloximes were also found to be good reagents for synthesis of amines from organomagnesium, -copper and -zinc reagents. 

Other Applications. Hydroxylainine-O-sulfonic acid has many applications in the area of organic synthesis. The acid has found application in the preparation of hydrazines from amines, aliphatic amines from activated methylene compounds, aromatic amines from activated aromatic compounds, amides from esters, and oximes. 

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