3-Mercaptopropionitrile

3-Mercaptopropionitrile
Names
	Preferred IUPAC name 3-Sulfanylpropanenitrile
	Other names β-Mercaptopropionitrile, 2-Cyanoethanethiol, 3-Mercaptopropanenitrile
Identifiers
CAS Number	1001-58-7 ;
3D model (JSmol)	Interactive image;
ChemSpider	63654;
ECHA InfoCard	100.012.438
EC Number	213-682-1;
PubChem CID	70477;
UNII	KTV2WN28SV ;
CompTox Dashboard (EPA)	DTXSID4061383 ;
	InChI InChI=1S/C3H5NS/c4-2-1-3-5/h5H,1,3H2 Key: FCTXEFOUDMXDPD-UHFFFAOYSA-N;
	SMILES C(CS)C#N;
Properties
Chemical formula	C3H5NS
Molar mass	87.14 g·mol−1
Appearance	Colorless liquid
Density	1.0696 g/cm3
Boiling point	30–32 °C (86–90 °F; 303–305 K) 0.08-0.12 mm
Hazards
	GHS labelling:
Pictograms
Signal word	Warning
Hazard statements	H302, H312, H315, H319, H332, H335
Precautionary statements	P261, P264, P270, P271, P280, P301+P312, P302+P352, P304+P312, P304+P340, P305+P351+P338, P312, P321, P322, P330, P332+P313, P337+P313, P362, P363, P403+P233, P405, P501
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

3-Mercaptopropionitrile is the organosulfur compound with the formula HSCH₂CH₂CN.^[1] Containing both thiol and nitrile functional groups, it is a bifunctional compound. A colorless liquid, the compound has found some use as a masked form of thiolate.

Preparation and reactions

it is typically prepared from 3-chloropropionitrile via initial reaction with thiourea. The resulting isothiouronium salt hydrolyzes to the thiol.^[2] A variation on this preparation involves isolation of the disulfide (SCH₂CH₂CN)₂. Zinc reduction of this disulfide gives the thiol.^[3]

Thioethers derived from S-alkylation of 3-mercaptopropionitrile react with strong bases to give thiolate and acrylonitrile:

RSCH₂CH₂CN + KOBu-t → RSK + CH₂=CHCN + HOBu-t

The conversion illustrates the retro-Michael reaction. The thiolate is then hydrolyzed

RSK + H⁺ → RSH + K⁺

References

^ Encyclopedia of Reagents for Organic Synthesis (1 ed.). Wiley. 2001-04-15. doi:10.1002/047084289x.rn02347. ISBN 978-0-471-93623-7. S2CID 242662674.
^ R. Eric Gerber; Carlos Hasbun; Larisa G. Dubenko; Mei Fong King; Donald E. Bierer (2000). "β-Mercaptopropionitrile". Organic Syntheses. 77: 186. doi:10.15227/orgsyn.077.0186.
^ Klose, J.; Reese, C. B.; Song, Q. (1997). "Preparation of 2-(2-cyanoethyl)sulfanyl-1H-isoindole-1,3-(2H)-dione and related sulfur-transfer agents". Tetrahedron. 53 (42): 14411–14416. doi:10.1016/S0040-4020(97)00924-1.

[1] Encyclopedia of Reagents for Organic Synthesis (1 ed.). Wiley. 2001-04-15. doi:10.1002/047084289x.rn02347. ISBN 978-0-471-93623-7. S2CID 242662674.

[2] R. Eric Gerber; Carlos Hasbun; Larisa G. Dubenko; Mei Fong King; Donald E. Bierer (2000). "β-Mercaptopropionitrile". Organic Syntheses. 77: 186. doi:10.15227/orgsyn.077.0186.

[3] Klose, J.; Reese, C. B.; Song, Q. (1997). "Preparation of 2-(2-cyanoethyl)sulfanyl-1H-isoindole-1,3-(2H)-dione and related sulfur-transfer agents". Tetrahedron. 53 (42): 14411–14416. doi:10.1016/S0040-4020(97)00924-1.

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