P-Chloranil

A test for secondary amines (e.g. proline) is the Chloranil test (1 drop of a 2% acetaldehyde solution in DMF, followed by one drop of a 2% solution of p-chloranil in DMF, leave for 5 mins). A positive test gives blue stained beads. 

The yield of substituted quinoline 27 was substantially improved when p-chloranil... 

Dipping solution Dissolve O.S g p-chloranil in 90 ml ethyl acetate, cautiously make up to 100 ml with 10 ml sulfuric acid (ca. 96<9b) and homogenize for S min in the ultrasonic bath or by vigorous shaking. 

Spray solution II For aromatic amines Dissolve 200 mg p-chloranil in 100 ml chlorobenzene [1]. 

Secondary amines react at room temperature with acetaldehyde and p-chloranil according to the following scheme to yield intensely blue-colored dialkylaminovinylquinone derivatives [2] ... 

In the case of tertiary N-ethylamine derivatives the N-ethyl group is first selectively oxidized by p-chloranil to an enamino group which then condenses with excess p-chloranil to a blue aminovinylquinone derivative [7]. Secondary N-ethyl derivatives do not yield blue aminovinylquinone derivatives they probably react directly with chloranil by nucleophihc attack at one of the four chlorine atoms to yield aminoquinones of other colors [7], It has also been suggested that some classes of substances react to yield charge transfer complexes [1, 5, 8, 12],... 

Amines (primary and secondary aromatic) p-Chloranil The reaction depends on the catalytic effect of silica gel. Monochlorobenzene, as solvent for the reagent, also contributes. There is no reaction on cellulose layers. [17, 22]... 

Khashaba et al. [34] suggested the use of sample spectrophotometric and spectrofluorimetric methods for the determination of miconazole and other antifungal drugs in different pharmaceutical formulations. The spectrophotometric method depend on the interaction between imidazole antifungal drugs as -electron donor with the pi-acceptor 2,3-dichloro-5,6-dicyano-l,4-benzoquinone, in methanol or with p-chloranilic acid in acetonitrile. The produced chromogens obey Beer s law at Amax 460 and 520 nm in the concentration range 22.5-200 and 7.9-280 pg/mL for 2,3-dichloro-5,6-dicyano-l,4-benzoquinone and p-chloranilic acid, respectively. Spectrofluorimetric method is based on the measurement of the native fluorescence of ketoconazole at 375 nm with excitation at 288 nm and/or fluorescence intensity versus concentration is linear for ketoconazole at 49.7-800 ng/mL. The methods... 

More recently, an environmentally benign method using air as oxidant has been developed for the oxidative cyclization of arylamine-substituted tricarbonyl-iron-cyclohexadiene complexes to carbazoles (Scheme 19). Reaction of methyl 4-aminosalicylate 45 with the complex salt 6a affords the iron complex 46, which on oxidation in acidic medium by air provides the tricarbonyliron-complexed 4a,9a-dihydrocarbazole 47. Aromatization with concomitant demetalation by treatment of the crude product with p-chloranil leads to mukonidine 48 [88]. The spectral data of this compound are in agreement with those reported by Wu[22j. 

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