Diacetyl dioxime

The diacetyl monoxime condenses readily with hydroxylamine hydrochloride or sulphate with the formation of dimethylglyoxime (diacetyl dioxime) ... 

HaC.C( NO. CH 3).C( N.0. CH 3).CH3 mw 144.17, N 19.43% crysts (from ale), pltits (by condensation), mp 41—44°, hp 158.5° at 780mm press obtd by reacting diacetyl-dioxime with dimethylsulfate in NaOH, and and by another method of Thilo (Refs 3 4) On treating it with fuming nitric acid it. gave a small amt of white ppt which was not identified... 

Some examples are titration of Pb2+ with CrO -, Ni2+ with diacetyl-dioxime, and barbituric acids with Hg2(C104)2. 

Spectrophotometric determination with diacetyl dioxime (dimethylglyoxime)... 

Transfer to a 100-ml measuring flask either 50 ml of the water sample or a smaller quantity which has been made up to 50 ml with distilled water (nickel content 0.001 to 0.25 mg). Add 10 ml of bromine water and shake. Add one after the other 8 ml of triethanolamine, 12 ml of concentrated ammonium hydroxide solution and ml of diacetyl dioxime solution and... 

Next treat the hydrochloric solution containing the nickel with 3 ml of diacetyl dioxime solution, 1 ml of 10 m sodium hydroxide solution and 0.3 ml of ammonium peroxodisulphate solution, mixing well each time. Dilute with water to the mark at 20 C, leave to stand for about 2 hours, and measure in a 3-cm cuvette at 60 nm against distilled water. Carry out a blank test concurrently and take into account accordingly. 

After adding diacetyl dioxime (dimethylglyoxime) solution, nickel ions are extracted from citrate-buffered solution with chloroform, re-extracted with 1 m hydrochloric acid from the organic phase and determined by means of atomic-absorption analysis. 

Dissolve 15 g diacetyl dioxime (disodium salt) (C/ H6N2Na202 8 H2O) in water and make up to 1000 ml... 

Add 5 ml diacetyl dioxime solution and 15 ml chloroform and shake well for 2 minutes. 

Nickel forms complexes in aqueous solutions in which negative groups or neutral polar molecules are attached to Ni. A well-known complex is the red nickel diacetyl dioxime. 

Diacetyl monoxime (I) condenses with hydroxylamine to produce diacetyl dioxime (dimethylglyoxime) the well known reagent for nickel. Consequently, if the condensation occurs in the presence of an ammoniacal nickel solution, the familiar red, slightly soluble nickel dimethylglyoxime (II) is formed directly from the components ... 

In these reactions the tested organic substance and an inorganic salt give a more or less stable strong color due to a complex salt. In Part 2 of this monograph a series of such reactions is described, such as, for example, the reaction of hydroxamic acids with ferric salts (p. 276), the reaction of phenols with ferric chloride (p. 188), the reaction of molybdenum with o-dihydro-xybenzenes (p. 191), of diacetyl dioxime with nickel salts (p. 227), of phenols with Millon s reagent (p. 196), alcohols with ceric ammonium nitrate (p. 170), alcohols with vanadium-hydroxy quinoline complex (p. 171), and the reaction of cis-enols of )5-dicarbonylic compounds and a-dicarbonyl compounds with ferric chloride, (p. 294.)... 

Diacetyl dioxime Diacetyl monoxime Benzaldehyde semi-carbazone... 

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