Organic compound with formula CH2(CN)2
Malononitrile
Skeletal formula of malononitrile
Names
IUPAC name
Preferred IUPAC name
Other names
Malonodinitrile, Cyanoacetonitrile, Dicyanomethane, Malonic dinitrile
[ 1]
Identifiers
773697
ChEBI
ChemSpider
ECHA InfoCard 100.003.368
EC Number
1303
MeSH
dicyanmethane
RTECS number
UNII
UN number
2647
InChI=1S/C3H2N2/c4-2-1-3-5/h1H2
Y Key: CUONGYYJJVDODC-UHFFFAOYSA-N
Y
Properties
CH2 (CN)2
Molar mass
−1
Appearance
Colourless or white solid[ 1]
Density
1.049 g cm−3
Melting point
32 °C; 89 °F; 305 K
Boiling point
220.1 °C; 428.1 °F; 493.2 K
13% (20 °C)[ 1] [clarification needed
Thermochemistry
110.29 J K−1 mol−1
130.96 J K−1 mol−1
187.7 to 188.1 kJ mol−1
−1,654.0 to −1,654.4 kJ mol−1
Hazards
GHS labelling
Danger
H301 , H311 , H331 , H410
P261 , P273 , P280 , P301+P310 , P311
Flash point
86 °C (187 °F; 359 K)
Lethal dose or concentration (LD, LC):
19 mg kg−1 (oral, mouse) 350 mg kg−1 (dermal, rat)
NIOSH
none[ 1]
TWA 3 ppm (8 mg/m3 )[ 1]
N.D.[ 1]
Related compounds
Related alkanenitriles
Related compounds
Malonic acid
Except where otherwise noted, data are given for materials in their
standard state (at 25 °C [77 °F], 100 kPa).
Chemical compound
Malononitrile is an organic compound nitrile with the formula CH2 (CN)2 . It is a colorless or white solid, although aged samples appear yellow or even brown. It is a widely used building block in organic synthesis .
Preparation and reactions
It can be prepared by dehydration of cyanoacetamide .[ 3] [citation needed Most commonly malononitrile is produced by the gas-phase reaction of acetonitrile and cyanogen chloride :[ 4]
NCCl + CH3 CN → NCCH2 CN + HCl About 20,000,000 kg are produced annually (2007). Important outlets include the synthesis of thiamine , the drug triamterene and minoxidil , and the dyes disperse Yellow 90 and disperse Blue 354.[ 4]
Malononitrile is relatively acidic, with a pK a of 11 in water.[ 5] Knoevenagel condensation , for example in the preparation of CS gas :
CS-chemical-synthesis Despite its relative obscurity, Malononitrile is very useful in several reactions, the prime example being a suitable starting reagent for the Gewald reaction , where the nitrile condenses with a ketone or aldehyde in the presence of elemental sulfur and a base to produce a 2-aminothiophene .[ 6]
Interstellar occurrence
Due to its permanent dipole moment (i.e., 3.735 ± 0.017 D)[ 7] spectral emissions coming from interstellar cloud TMC-1 through the QUIJOTE line survey conducted with the Yebes 40 m radio telescope .[ 8] [ 9]
References
^ a b c d e f NIOSH Pocket Guide to Chemical Hazards. "#0378" . National Institute for Occupational Safety and Health (NIOSH). ^ a b International Union of Pure and Applied Chemistry (2014). Nomenclature of Organic Chemistry: IUPAC Recommendations and Preferred Names 2013 . The Royal Society of Chemistry . p. 902. doi :10.1039/9781849733069 . ISBN 978-0-85404-182-4 ^ Surrey, Alexander (1945). "Malononitrile". Organic Syntheses . 25 : 63– 64. doi :10.15227/orgsyn.025.0063 . ^ a b Strittmatter, Harald; Hildbrand, Stefan; Pollak, Peter (2007). "Malonic Acid and Derivatives". Ullmann's Encyclopedia of Industrial Chemistry . doi :10.1002/14356007.a16_063.pub2 . ISBN 978-3527306732 ^ Evans pK a table ^ Sabnis, R. W.; Rangnekar, D. W.; Sonawane, N. D. (1999). "2-Aminothiophenes By The Gewald Reaction" . Journal of Heterocyclic Chemistry . 36 (2): 333– 345. doi :10.1002/jhet.5570360203 . Retrieved 2007-07-18 . ^ Hirota, Eizi; Morino, Yonezo (1960-02-01). "Microwave Spectrum of Malononitrile, CH2(CN)2. I. The Molecular Structure in the Ground Vibrational State" . Bulletin of the Chemical Society of Japan . 33 (2): 158– 162. doi :10.1246/bcsj.33.158 . ISSN 0009-2673 . ^ Agúndez, M.; Bermúdez, C.; Cabezas, C.; Molpeceres, G.; Endo, Y.; Marcelino, N.; Tercero, B.; Guillemin, J.-C.; de Vicente, P.; Cernicharo, J. (August 2, 2024). "The rich interstellar reservoir of dinitriles: Detection of malononitrile and maleonitrile in TMC-1" . Astronomy & Astrophysics . 688 : L31. arXiv :2408.02843 doi :10.1051/0004-6361/202451525 . ISSN 0004-6361 . Retrieved January 7, 2025 . ^ Victoria Corless (2024-11-12). "Scientists found 'nitriles' in an interstellar cloud — here's why that could be huge" . Space.com . Retrieved 2025-01-07 .
External links
