Isothioicyanate d’Allyat — Wikipedia
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Isothiocyanate d’allyle | ||
Identification | ||
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UICPA name | 3-Isothiocyanatoprop-1-ène | |
N O CAS | ||
N O Echa | 100,000.281 | |
N O THIS | 200-309-2 | |
Pubchem | 5971 | |
SMILES | ||
Inches |
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Appearance | Colorless oily liquid | |
Chemicals | ||
Formula | C 4 H 5 NS [Isomers] | |
Molar mass [ first ] | 99,154 ± 0.009 G/MOL C 48,45 %, H 5,08 %, N 14,13 %, S 32,34 %, |
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Physical properties | ||
T° fusion | −103,15 °C [ 2 ] | |
T° boiling | 151.9 °C [ 2 ] | |
Volumic mass | 1.02 g · cm -3 [ 3 ] | |
T° d’auto-inflammation | 250 °C (decomposition) [ 3 ] | |
Flash point | 48 °C [ 3 ] | |
Thermochimie | ||
C p | 156.9 J · mol -first · K -first (liquid, 16.85 °C ) [ 2 ] | |
Precautions | ||
NFPA 704 [ 4 ] | ||
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Directive 67/548/EEC [ 3 ] | ||
T N |
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Transport [ 3 ] | ||
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Ecotoxicology | ||
DL 50 | 308 mg · kg -first (mouse, oral) 80 mg · kg -first (mouse, s.c.) [ 5 ] |
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LogP | 2.15 [ 5 ] | |
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IS units and CNTP , unless otherwise stated. | ||
modifier |
L’ isothiocyanate d’allyle is an organo-sulfuré compound of semi-developed formula 2 CHCH 2 Ncs. This colorless oil is responsible for the spicy taste of mustard, horseradish and wasabi. It is little soluble in water but much more in most organic solvents [ 6 ] .
Allyle isothiocyanate comes from black mustard seeds ( Brassica nigra ) or brown mustard ( Brassica juncea ). When these seeds are crushed, an enzyme is released, myrosinase, which reacts on sinigrine (a glucosinolate) to give allyl isothiocyanate (principle formerly used in sinapisms).
Allyle isothiocyanate is used for plants as a defense against herbivores. As it is also toxic to the plant itself, it is stored in the harmless form of glucosinolate and the enzyme which are separated. When an animal chews the plant, the allyl isothiocyanate is released and pushes the animal.
Allyle isothiocyanate is produced commercially by the reaction of allyle chloride with potassium thiocyanate [ 6 ] :
- CH 2 = CHCH 2 CL + KSCN → CH 2 = CHCH 2 NCS + KCl.
The product obtained in this way is also known as “synthetic mustard oil”. Allyle isothiocyanate can also be obtained by dry distillation of mustard seeds. The product obtained by this process is also called “volatile mustard oil” and its purity is around 92%. It is mainly used as an agent of flavor and food seasoning. Synthetic allyle isothiocyanate is used as insecticide, antibacterial or nematicide and, in some cases, to protect cultures [ 6 ] .
Allyle isothiocyanate hydrolysis gives allylamine [ 7 ] .
Allyle isothiocyanate is moderately toxic with DL 50 of 151 mg · kg -first But it is tear gas [ 6 ] .
- Molar mass calculated after ‘ Atomic weights of the elements 2007 » , on www.chem.qmul.ac.uk .
- (in) « Allyl isothiocyanate » , on NIST/WebBook , accessed September 28, 2009
- Entrance “Allyl isothiocyanate” in the chemical database Achievement IFA (German organization responsible for occupational safety and health) ( German , English ), access on September 28, 2009 (Javascript required)
- UCB University of Colorado
- (in) ‘ Isothiocyanate d’allyle » , on Chedplus , accessed September 28, 2009
- F. Romanowski; H. Klenk, “Thiocyanates and Isothiocyanates, Organic” in Ullmann’s Encyclopedia of Industrial Chemistry, 2005, Wiley-VCH: Weinheim.
- M. T. Leffler, Allylamine , Org. Synth., coll. « vol. 2 », , p. 24
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