Carboxylic acids with potassium dichromate

The reaction of 2-nitrodibenz[6,/]oxepin-10-carboxylic acid with potassium dichromate in acetic acid takes a rather unexpected course 9-methyl-2-nitroxanthene (2) is formed by loss of the carboxylic group and ring contraction.107... 

Primary alcohols are readUy oxidised to carboxylic acids with common oxidising agents such as potassium permanganate (KMn04) in neutral, acidic or alkaline media or by potassium dichromate (K2Cr207) and chromium trioxide (CrOg) in acidic media (Jones reagent). 

The oxidative cleavage of alkenes resulting in the formation of carboxylic acids is also accomplished with chromium trioxide in sulfuric acid or acetic acid [567, 569] with potassium dichromate in sulfuric acid [1111] and with ruthenium tetroxide, generated in situ from ruthenium trichloride... 

Aliphatic carboxylic acids are fonned from primary alcohols or aldehydes by reflux with potassium dichromate (VI) acidified with sulphuric acid. 

An alcohol was converted to a carboxylic acid with ARis acidic potassium dichromate. A 4.46-g sample of the acid was added to 50.0 rtiL of 2.27 M NaOH and the excess NaOH required 28.7 mL of 1.86 M HCl for neutralization. What is the molecular formula of the alcohol ... 

Cobalt(II) acetate in conjunction with 9,10-dibromoanthracene is an efficient catalyst for the oxidation of 2-methylthiophenes (Scheme 99) (72ZOR2590, 74ZOB837). As mentioned in Section 3.02.3.3, aqueous potassium dichromate has been used for the oxidation of 3-methylthiophene to the corresponding carboxylic acid in 80-85% yield (65JOC1453). Alkaline KMn04 oxidation of alkylthiophenes gives low yields of the acids (52HC(3)364>. 

Carboxylic acids can be obtained from most alkylbenzenes b" oxidation of the side chain with reagents such as potassium permanganate, potassium dichromate, or nitric acid ... 

Solution Carboxylic acids can be prepared by a variety of ways. One can employ direct oxidation with potassium permanganate, KMnOi, or potassium dichromate, K2Cr207, on primary alcohols and aldehydes. KMnOu may also be used to oxidize alkyl substituents on a benzene ring to the carboxyl group. Carboxylic acids can also be prepared by carbonation of Grignard reagents, and hydrolysis of nitriles. 

Draw the structural formula of a compound with the given molecular formula that, upon oxidation by potassium dichromate in aqueous sulfuric acid, gives the carboxylic acid or dicarboxylic acid shown. 

The ethanal formed can be further oxidised to form ethanoic acid, a carboxylic acid. This is achieved by refluxing with excess acidified potassium dichromate(VI) ... 

A primary alcohol can be further oxidised to a carboxylic acid by refluxing the alcohol with excess acidified potassium dichromate(Vl). 

Carboxylic acids can be formed from the oxidation of primary alcohols or aldehydes by refluxing with excess potassium dichromate(Vl) and dilute sulfuric(VI) acid. They can also be made by refluxing nitriles with dilute hydrochloric acid. 

The carboxylates of the 1- and 2-mole EO adducts of nonylphenol can be made by oxidizing the corresponding NPE with chromic acid in sulftiric acid. In a similar manner, carboxylated PEG can be prepared by oxidation of commercially available PEG with acidic potassium dichromate (86,99). An alternative path to nonylphenoxyacetic acid and its ethoxyacetic and diethoxyacetic acid analogs is reaction of nonylphenol and nonylphenol low mole ethoxylates with chloroacetate under alkaline conditions (51,94,100,140). Ring-brominated analogs are made by reaction of the isolated standard with bromine water (94). 2,4,4-Trimethyl-2-pentanol can be produced by hydration of 2,4,4-trimethylpentene (94). 

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