Cyanoacetamide

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Structural formula
Structural formula of cyanoacetamide
General
Surname Cyanoacetamide
other names
  • 2-cyanoacetamide
  • Cyanomethylformamide
  • 3-nitrilo-propionamide
Molecular formula C 3 H 4 N 2 O
Brief description

pale yellowish to white solid

External identifiers / databases
CAS number 107-91-5
EC number 203-531-8
ECHA InfoCard 100.003.211
PubChem 7898
Wikidata Q1146906
properties
Molar mass 84,077
Physical state

firmly

density

1.061-1.062g · cm -3

Melting point

119-120 ° C

solubility
  • little in ethanol (1.3g l −1 at 20 ° C)
  • good in water (150g l −1 at 20 ° C)
safety instructions
GHS labeling of hazardous substances
07 - Warning

Caution

H and P phrases H: 302-315-319-335
P: 261-305 + 351 + 338
Toxicological data

<7230 mg kg −1 ( LD 50 ,  rat ,  oral )

As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Cyanoacetamide is a solid and a derivative of acetic acid. As an amide of cyanoacetic acid, it has a nitrile group , a CH-acidic methylene group and an amide function in the molecule.

Extraction and presentation

Cyanoacetamide is obtained in 86-88% yield by reacting ethyl cyanoacetate with concentrated aqueous ammonia .

Production of cyanoacetamide from ethyl cyanoacetate and ammonia

A more recent synthesis is the reaction of haloacetamides with alkali cyanides in the presence of water.

Chemical properties

The acidic hydrogen atoms in cyanoacetamide react easily with formaldehyde or with halogens . Because of its reactivity and multifunctionality, cyanoacetamide is a starting material for the synthesis of heterocycles , for example .

use

Cyanoacetamide is used as the starting material for the production of malonic acid dinitrile , the amide group being dehydrated to the nitrile group by reaction with phosphorus pentachloride (PCl 5 ) or phosphoryl chloride (POCl 3 ). The reaction can also be carried out in 1,2-dichloroethane as a solvent.

Production of malononitrile from cyanoacetamide

The conversion with bromine leads to the - meanwhile obsolete - biocide 2,2-Dibromcyanacetamid DBNPA.

Bromination of cyanoacetamide

The cyclocondensation of 1,3-diketones with cyanoacetamide produces 3-cyano-2-pyridones in a Guareschi-Thorpe reaction . Subsequent hydrolysis of the cyano group in aqueous acid, decarboxylation, chlorination and catalytic hydrogenation leads to 2,4-dialkylpridines.

Cyclization of cyanoacetamide with 1,3-diketones

A synthetic route to the gout drug allopurinol starts from cyanoacetamide, which with formamidine and subsequent ring closure with hydrazine results in a substituted pyrazole which is cyclized with formamide to give pyrazolopyrimidine allopurinol.

In the syntheses of the antituberculotics ethionamide and the homologous prothionamide , cyanoacetamide is used as the starting material.

Individual evidence

  1. ↑ a b c d B. B. Corson, RW Scott, and CE Vose: Cyanoacetamide In: Organic Syntheses . 9, 1929, p. 36, doi : 10.15227 / orgsyn.009.0036 ; Coll. Vol. 1, 1941, p. 179 ( PDF ).
  2. ↑ a b c Data sheet cyanacetamide (PDF) from Merck , accessed on February 13, 2010.
  3. ↑ a b Cyanoacetamide data sheet from Sigma-Aldrich , accessed on February 24, 2018 ( PDF ).
  4. ↑ Patent DE2538254C2 : Process for the production of cyanoacetamides. Registered on August 28, 1975 , published on June 7, 1984 , applicant: BASF AG , inventor: Hans-Jürgen Quadbeck-Seeger . ‌
  5. ↑ BB Corson, RW Scott, and CE Vose: Malononitrile In: Organic Syntheses . 10, 1930, p. 66, doi : 10.15227 / orgsyn.010.0066 ; Coll. Vol. 2, 1943, p. 379 ( PDF ).
  6. ↑ Alexander R. Surrey: Malononitrile In: Organic Syntheses . 25, 1945, p. 63, doi : 10.15227 / orgsyn.025.0063 ; Coll. Vol. 3, 1955, p. 535 ( PDF ).
  7. ↑ Eberhard Breitmaier, Günther Jung: Organic chemistry . 5th, revised. Edition. Thieme, Stuttgart, New York 2005, ISBN 3-13-541505-8 .
  8. ↑ A. Kleemann , J. Engel: Pharmaceutical active ingredients , 2nd edition, Georg Thieme, Stuttgart - New York, 1982.