Hydrazides

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Organic hydrazides
Acyl Acide General Structure V.1.png
Carboxylic acid hydrazide with the functional group marked blue (R = organyl group , e.g. alkyl or aryl group ).
Sulfonyl Acide General Structure V.1.png
Sulphonic acid hydrazide with the functional group marked blue (R = organyl group, e.g. alkyl or aryl group).

Hydrazides are a class of compounds which have a functional group have, in the two nitrogen -atoms via a covalent bond associated with no or up to four substituents may have, depending on whether it out of the ground substance hydrazine or of organic hydrazines formed were. The organic hydrazides, as derivatives of carboxylic acids, are either carboxylic acid hydrazides and then have at least one acyl group as a substituent or they are as derivatives of sulfonic acids , that is sulfonic acid hydrazides and then have at least one sulfonyl group as a substituent .

Inorganic hydrazides

Salt- like compounds derived from hydrazine (NH 2 –NH 2 ) such as sodium hydrazide (NaNH – NH 2 ) decompose with the ingress of air or moisture with an explosion. Inorganic hydrazides are obtained by reacting metals or metal compounds with hydrazine.

Organic hydrazides

Carboxylic acid hydrazides can be prepared by reacting carboxylic acid esters with hydrazine. p -Toluenesulfonyl hydrazide can be prepared by reacting p -tosyl chloride with hydrazine .

use

Girard reagent T, a water-soluble acyl hydrazide

The reaction of carboxylic acid hydrazides with nitrous acid (HNO 2 ) yields carboxylic acid azides (acyl azides), which are of preparative importance in Curtius degradation - a process for the synthesis of primary amines .

The reaction of carboxylic acid hydrazides with ketones or aldehydes leads to crystallizable hydrazones . With the water-soluble carboxylic acid hydrazides "Girard reagent P or T", the isolation of hormones from aqueous vital solutions was successful in the 1930s.

p -Toluenesulfonylhydrazide is a useful reagent in organic chemistry, for example in the Shapiro reaction .

Individual evidence

  1. ^ Brockhaus ABC Chemie , VEB FA Brockhaus Verlag Leipzig 1965, p. 557.
  2. ^ Organikum , Wiley-VCH Verlag GmbH, 23rd edition, 2009, p. 465, ISBN 978-3-527-32292-3 .
  3. ^ Lester Friedman, Robert L. Litle, Walter R. Reichle: p-Toluenesulfonylhydrazide In: Organic Syntheses . 40, 1960, p. 93, doi : 10.15227 / orgsyn.040.0093 ; Coll. Vol. 5, 1973, p. 1055 ( PDF ).
  4. ^ Siegfried Hauptmann : Organic Chemistry , 2nd reviewed edition, VEB Deutscher Verlag für Grundstoffindustrie, Leipzig, 1985, p. 426, ISBN 3-342-00280-8 .

Web links

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