Rimini test

Advantage is taken of this decomposition in carrying out the Angeli-Rimini test for aldehydes (p. 214). 

When a secondary amine is treated with sodium nitroprusside (Na2[Fe(CN)5NO]) in the presence of acetaldehyde, acetone, pyruvic acid, etc., blue to violet compounds of unknown structure are obtained This is the so-called Rimini test . A colourimetric... 

A method based on quatemisation was proposed for the detection of j8-hydroxyethylamines , which can be possibly extended to other j8-substituted ethylamines. It consists of heating the amine with sodium chloroacetate. A betaine is first formed (equation 13), which decomposes on further heating, yielding acetaldehyde (equation 14). The latter can be detected with a morpholine-sodium nitroprusside solution (compare with the Rimini test in section II.B.3). 

Sodium nitroprusside/acetaldehyde (Rimini test) Secondary aliphatic and... 

ANGELI RIMINI HydroxamlcAcidSynthesis Synthesis of hydroxamlc acids from aldehydes and N suMonylhydroxytamine, also used as a color test for aldehydes... 

The reaction is based on an early observation by Angeli and Ahrens that Piloty s acid converted aldehydes to hydroxamic acids, and this has formed the basis of the Angeli-Rimini aldehyde test. Di Maio and Tardella propose the above reaction sequence, consistent with the observed second-order kinetics. The possibility that benzenesulfon-hydroxamic acid would decompose in alkali to give nitroxyl (HNO)... 

Detection and Determination of the Alcohol.—1. Qualitative. 100 c.c. of the vinegar, neutralised exactly with sodium hydroxide (towards litmus paper), are distilled, the first 4-5 c.c of distillate being tested for alcohol by Rimini s reaction see Varnishes). 

Rimini s test (for primary aliphatic amines). To a suspension or solution of 1 drop of the compound or to an equivalent quantity of its solution in 3 ml of water, add 1 ml of pure acetone and 1 drop of a freshly prepared 1 per cent aqueous solution of disodium pentacyanonitrosoferrate(m) (nitroprusside). A violet-red colour will develop within 1 minute. 

Angelo Angeli s name, along with that of Enrico Rimini (1874—1917), is often associated with the chemical reaction that bears their names. In 1896 Angeli, and independently Rimini, discovered the reaction between an aldehyde and a sulfonamide to form a hydroxamic acid they published their discoveries in the same year [115, 116]. The reaction was mainly used as a chemical test in the dairy industry for detecting the presence of aldehydes as a consequence of food storage. The Angeli-Rimini reaction has been recently applied in solid-phase synthesis [117]. 

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