Acid chlorides sulfonic acids

Procure building blocks Purchase or synthesize amines, acids, acid chlorides, sulfonic acids, and sulfonyl chlorides... 

Zinc chloride is a Lewis acid catalyst that promotes cellulose esterification. However, because of the large quantities required, this type of catalyst would be uneconomical for commercial use. Other compounds such as titanium alkoxides, eg, tetrabutoxytitanium (80), sulfate salts containing cadmium, aluminum, and ammonium ions (81), sulfamic acid, and ammonium sulfate (82) have been reported as catalysts for cellulose acetate production. In general, they require reaction temperatures above 50°C for complete esterification. Relatively small amounts (<0.5%) of sulfuric acid combined with phosphoric acid (83), sulfonic acids, eg, methanesulfonic, or alkyl phosphites (84) have been reported as good acetylation catalysts, especially at reaction temperatures above 90°C. 

Aromatic sulfonyl chlorides can be prepared directly, by treatment of aromatic rings with chlorosulfuric acid. ° Since sulfonic acids can also be prepared by the same reagent (11-7), it is likely that they are intermediates, being converted to the halides by excess chlorosulfuric acid. The reaction has also been effected with bromo-and fluorosulfuric acids. 

At high pH (> 10-11) saponification of the sulfonyl chloride to the sodium salt of 3-amino-3-methylbutyric acid-N-sulfonic acid will predominate, and at too low a pH (e.g., pH of 0) hydrolysis to 3-hydroxy-3-methylbutyramide will prevail. 

Activation of Carboxylic Acids with Sulfonic Acid Chlorides... 

Aryl chloride Aryl iodide Aryl selenic acid Aryl sulfonic acid Azide... 

Carboxylic acids and sulfonic acids are converted into acid chlorides in satisfactory yield ... 

In considering the synthesis of this compound several alternatives are possible. Two will be considered. Aniline may be sulfo-nated to sulfanilic acid, and after acetylation the chloride may be prepared by the action of phosphorus pentachloride. The acyl chloride, on ammonolysis, will give the acetylated sulfonamide. The other possibility is to use chlorosulfonic acid and introduce the sulfo and chloro groups simultaneously. Aniline is acetylated, and the acetanilide is sulfonated with excess of chlorosulfonic acid. The sulfonic acid group is introduced first, and by further reaction the acid chloride is formed ... 

Preferably the reaction in accordance with the invention is performed in the presence of a suitable catalyst, proton acids such as for instance haloid acids, sulfuric acid, phosphoric acid, perchloric acid, organic sulfonic acids, such as for instance methanesulfonic acid and p-toluenesulfonic acid, carboxylic acids, such as for instance oxalic acid, trifluoroacetic acid and other Lewis acids, such for instance boron trifluoride, ferric chloride, zinc chloride, zinc bromide, stannic chloride, titanium chloride or iodine having proved to be suitable. Furthermore mixtures of the individual catalysts may be used in certain cases. 

Sulfinic acids from sulfonic acid chlorides... 

Methods of working up the reaction mixtures vary greatly according to the nature of the azo compound. Acid dyes (sulfonic acids) can often be salted out as sodium salts by copious addition of sodium chloride. Basic dyes can in many cases be isolated as their hydrochlorides by addition of hydrochloric acid and sodium chloride. Hydroxy azo dyes are mostly sparingly soluble and are precipitated during the reaction. 

Sulfonyl chlorides. Sulfonic acids can be converted in satisfactory yield into sulfonyl chlorides via pyridinium sulfonates. Aminobenzenesulfonic acids can be converted quantitatively into pyridinium acetamidobenzenesulfonates by... 

Anhydrous MeOH in the presence of an electrophilic catalyst, such as HCl, concentrated sulfuric acid, dichloroacetic acid, trifluoroacetic acid, benzene sulfonic acid, polyphosphoric acid, p-toluene sulfonic acid, thionyl chloride, and perchloric acid is often used for the methylation of fatty acids. 

Hydrogen chloride Sulfonic acid chlorides from sulfinic acids... 

As was the etise with the earlxixylie acids, the sulfonic acids, also, may be converted into acyl chlorides and identified as such or in the form of the amides. Since sulfonic acids and their salts usually crystallize with water of ciystallization, it is important that the be dried for some time at 100° before subjeeting them to the treatment with phosphorus ijontachloride. The presence of other groups (such as OH, NH2, etc.), which also react with PCI5, will be expected to interfere with the preparation of the acyl chlorides. 

Zinc chloride s. under CI2CHOCH3 Dimethijlformamide s. under SOCI2 a,a-Dichloromethyl ether/zinc chloride Sulfonic acid chlorides from sulfonic acids... 

The relative rates of sulfonation of sulfonyl chlorides, sulfonic acids and sulfonate anions with chlorosulfonic acid follow the order ... 

Acetamidothiazole and its 4-alkyl derivatives react with chloro-sulfonic acid. The structure of the resulting products was a subject of controversy (172. 393-397). N-acetyl-A -(2-thiazolyl)-sulfamoyl chlorides (189) first proposed were then shown to be 2-acetamido-5-chloro-sulfonylthiazoles (190) (Scheme 120) (367. 368. 398). the latter assignment is based on infrared (368) and chemical evidence (367). 

Alkyl sulfonates are derivatives of sulfonic acids m which the proton of the hydroxyl group is replaced by an alkyl group They are prepared by treating an alcohol with the appropriate sulfonyl chloride usually m the presence of pyridine... 

Very strongly deactivating 0 II —CCI —C=N —SO3H -CF3 —NO2 (acyl chloride) (cyano) (sulfonic acid) (trifluoromethyl) (nitro) Meta directing... 

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