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Other electrophilic aromatic substitution reactions can also be promoted with trifluoroacetic anhydride, including nitration, sulfonation and nitrosylation. [2] Similar to acetic anhydride, trifluoroacetic anhydride can be used as a dehydrating agent and as an activator for the Pummerer rearrangement. [4]
As the anhydride will form trifluoroacetic acid in contact with water, an excess of the anhydride also serves to remove the solvent from the peroxide reactant: [9] CF 3 COOCOCF 3 + H 2 O → 2 CF 3 COOH. A more dilute hydrogen peroxide solution (30%) can be used to form trifluoroperacetic acid for some reactions from trifluoroacetic acid. [2] CF
Trifluoroacetic acid in a beaker. TFA is the precursor to many other fluorinated compounds such as trifluoroacetic anhydride, trifluoroperacetic acid, and 2,2,2-trifluoroethanol. [4] It is a reagent used in organic synthesis because of a combination of convenient properties: volatility, solubility in organic solvents, and its strength as an ...
When using oxalyl chloride as the dehydration agent, the reaction must be kept colder than −60 °C to avoid side reactions. With cyanuric chloride [11] or trifluoroacetic anhydride [12] instead of oxalyl chloride, the reaction can be warmed to −30 °C without side reactions.
Trifluoroacetonitrile can be produced by dehydration of trifluoroacetamide with trifluoroacetic anhydride in pyridine or carbon tetrachloride. [2] [3] This synthesis route was first described by Frédéric Swarts in 1922. [4] Trifluoroacetonitrile can also be produced by reacting 1,1,1-trichloro-2,2,2-trifluoroethane and ammonia at 610 °C. [5]
Aside from acetic anhydride, trifluoroacetic anhydride and trifluoromethanesulfonic anhydride have been employed as activators. [4] Common nucleophiles besides acetates are arenes, alkenes, amides, and phenols. The usage of α-acyl sulfoxides and Lewis acids, such as TiCl 4 and SnCl 4, allow the reaction to proceed at lower temperatures (0 °C ...
The reaction is often carried out without a solvent (particularly when a large reagent excess of the alcohol reagent is used) or in a non-polar solvent (e.g. toluene, hexane) that can facilitate Dean–Stark distillation to remove the water byproduct. [4] Typical reaction times vary from 1–10 hours at temperatures of 60–110 °C.
Alcohol oxidation is a collection of oxidation reactions in organic chemistry that convert alcohols to aldehydes, ketones, carboxylic acids, and esters. The reaction mainly applies to primary and secondary alcohols. Secondary alcohols form ketones, while primary alcohols form aldehydes or carboxylic acids. [1] A variety of oxidants can be used.