Carboxylic Acids, Acid Anhydrides

6 Carboxylic Acids, Acid Anhydrides RCOOH, RCOOCOR  

reduction can lead to aldehydes or alcohols, and the choice of reducing reagent and reaction conditions dictate the formation of one or the other functional group. 

The reduction of unsymmetiical anhydrides is regioselective Hydride attack takes place on the carbonyl group that is vicinal to the most substituted carbon, as 

Contrary to another report [MM4], NaBH4 and UBH4 in THF are poorly regioselective in this case. 

A method involving the in situ transformation of carboxylic acids into acylfluorides that are reduced by NaBH4 in MeOH has been recently proposed [KN4], 

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ACID ANHYDRIDES OF ALIPHATIC CARBOXYLIC ACIDS Acid anhydrides of monobasic aliphatic acids may be prepared —... 

Group of plastics composed of resins produced by reactions of epoxides or oxiranes with compounds such as amines, phenols, alcohols, carboxylic acids, acid anhydrides and unsaturated compounds. 

The most general and useful application of sulfur tetrafluoride is replacement of carbonyl oxygen and hydroxy groups by fluorine. The reaction has broad scope and is effective with all carbonyl and hydroxy compounds. Alcohols are converted into monofluoro derivatives 1, aldehydes, ketones and quinones into gew-difluoro compounds 2 and 3, and carboxylic acids, acid anhydrides, acid halides and amides into trifluoromethyl compounds 4. 

Acid chlorides react with diorganocuprate reagents to form ketones (Following fig.). Like the Grignard reaction, an alkyl group displaces the chloride ion to form a ketone. However, unlike the Grignard reaction, the reaction stops at the ketone stage. The mechanism is believed to be radical based rather than nucleophilic substitution. The reaction does not occur with carboxylic acids, acid anhydrides, esters, or amides. 

Theoretically, the Karl Fischer reagent can be used for the determination of any organic functional group that will undergo a quantitative and stoichiometric reaction to produce or consume water under conditions that do not interfere with the titration. These include alcohols, carboxylic acids, acid anhydrides, carbonyl compounds, primary and secondary amines, nitriles, and peroxides. 

The reaction is neither specific nor selective, since many carboxylic acids, acid anhydrides, acid halides, acid amides and imides, trihalo compounds, and even lactones give the same reaction. Also many nitrogen-bearing compounds give a positive reaction. Some references suggest that a blank be prepared in whi the substance to be examined is treated as described, but without converting it into a hydroxamic acid, because some substances give a color reaction alone. ... 

Benzene-H methanol Carboxylic acids, acid anhydrides KOH in methanol, CH3OK in benzene + methanol... 

A thermoset polymer containing one or more epoxide groups and curable by reaction with amines, alcohols, phenols, carboxylic acids, acid anhydrides, and mercap-tans. It has been primarily used as a matrix resin in composites and adhesives. 

Any functional group lower in this figure can be prepared from any functional group above it by treatment with an appropriate oxygen or nitrogen nucleophile. An acid chloride, for example, can be converted to an acid anhydride, an ester, an amide, or a carboxylic acid. Acid anhydrides, esters, and amides, however, do not react with chloride ion to give acid chlorides. 

Reactions of Formaldehyde with Carboxylic Acids, Acid Anhydrides, Acyl Chlorides, and Esters... 

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