2-Aminopyridine

2-Aminopyridine
Names
	Preferred IUPAC name Pyridin-2-amine
	Other names 2-Pyridinamine; 2-Pyridylamine; α-Aminopyridine; α-Pyridylamine
Identifiers
CAS Number	504-29-0 ;
3D model (JSmol)	Interactive image; Interactive image;
ChEMBL	ChEMBL21619 ;
ChemSpider	10008 ;
ECHA InfoCard	100.007.263
EC Number	207-988-4;
PubChem CID	10439;
RTECS number	US1575000;
UNII	WSX981HEWU;
UN number	2671
CompTox Dashboard (EPA)	DTXSID0024505 ;
	InChI InChI=1S/C5H6N2/c6-5-3-1-2-4-7-5/h1-4H,(H2,6,7) Key: ICSNLGPSRYBMBD-UHFFFAOYSA-N ; InChI=1/C5H6N2/c6-5-3-1-2-4-7-5/h1-4H,(H2,6,7) Key: ICSNLGPSRYBMBD-UHFFFAOYAM;
	SMILES n1ccccc1N; c1ccnc(c1)N;
Properties
Chemical formula	C5H6N2
Molar mass	94.117 g·mol−1
Appearance	colourless solid
Melting point	59 to 60 °C (138 to 140 °F; 332 to 333 K)
Boiling point	210 °C (410 °F; 483 K)
Solubility in water	>100%
Hazards
	GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H301, H311, H312, H315, H319, H335, H411
Precautionary statements	P261, P264, P270, P271, P273, P280, P301+P310, P302+P352, P304+P340, P305+P351+P338, P312, P321, P322, P330, P332+P313, P337+P313, P361, P362, P363, P391, P403+P233, P405, P501
Flash point	68 °C; 154 °F; 341 K
	Lethal dose or concentration (LD, LC):
LD50 (median dose)	200 mg/kg (rat, oral); 50 mg/kg (mouse, oral)
	NIOSH (US health exposure limits):
PEL (Permissible)	TWA 0.5 ppm (2 mg/m3)
REL (Recommended)	TWA 0.5 ppm (2 mg/m3)
IDLH (Immediate danger)	5 ppm
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). verify (what is ?) Infobox references

2-Aminopyridine is an organic compound with the formula H₂NC₅H₄N. It is one of three isomeric aminopyridines. It is a colourless solid that is used in the production of the drugs piroxicam, sulfapyridine, tenoxicam, and tripelennamine.^[3] It is produced by the reaction of sodium amide with pyridine, the Chichibabin reaction.^[4]

Reactions

The bifunctionality of 2-aminopyridine is illustrated by this 1:2 adduct with maleic anhydride.^[5]

Although 2-hydroxypyridine converts significantly to the pyridone tautomer, the related imine tautomer (HNC₅H₄NH) is less important for 2-aminopyridine.

2-Aminopyridine catalyzes the conversion of maleic anhydride to 2,3-dimethylmaleic anhydride.^[6]

Toxicity

The acute toxicity is indicated by the LD50 = 200 mg/kg (rat, oral).

References

^ ^a ^b ^c ^d ^e ^f NIOSH Pocket Guide to Chemical Hazards. "#0026". National Institute for Occupational Safety and Health (NIOSH).
^ "2-Aminopyridine". Immediately Dangerous to Life or Health Concentrations (IDLH). National Institute for Occupational Safety and Health (NIOSH).
^ Rao RN, Chanda K (January 2022). "2-Aminopyridine - an unsung hero in drug discovery". Chemical Communications. 58 (3). Cambridge, England: 343–382. doi:10.1039/d1cc04602k. PMID 34904599.
^ Shimizu S, Watanabe N, Kataoka T, Shoji T, Abe N, Morishita S, et al. (2007). "Pyridine and Pyridine Derivatives". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a22_399. ISBN 978-3-527-30673-2.
^ Baumann ME, Bosshard H, Breitenstein W, Rihs G, Winkler T (1984). "Mechanismus der decarboxylativen Dimerisierung von Maleinsäureanhydrid zu Dimethylmaleinsäureanhydrid unter Einfluss von 2-Aminopyridin". Helvetica Chimica Acta. 67 (7): 1897–1905. doi:10.1002/hlca.19840670728.
^ Hood DK (2024). "Maleic Anhydride, Maleic Acid, and Fumaric Acid". Kirk-Othmer Encyclopedia of Chemical Technology. pp. 1–51. doi:10.1002/0471238961.1301120506051220.a01.pub3. ISBN 978-0-471-48494-3.

External links

[NIOSH-1] ^ ^a ^b ^c ^d ^e ^f NIOSH Pocket Guide to Chemical Hazards. "#0026". National Institute for Occupational Safety and Health (NIOSH).

[2] "2-Aminopyridine". Immediately Dangerous to Life or Health Concentrations (IDLH). National Institute for Occupational Safety and Health (NIOSH).

[Rao_2022-3] Rao RN, Chanda K (January 2022). "2-Aminopyridine - an unsung hero in drug discovery". Chemical Communications. 58 (3). Cambridge, England: 343–382. doi:10.1039/d1cc04602k. PMID 34904599.

[Shimizu_2007-4] Shimizu S, Watanabe N, Kataoka T, Shoji T, Abe N, Morishita S, et al. (2007). "Pyridine and Pyridine Derivatives". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a22_399. ISBN 978-3-527-30673-2.

[Baumann_1984-5] Baumann ME, Bosshard H, Breitenstein W, Rihs G, Winkler T (1984). "Mechanismus der decarboxylativen Dimerisierung von Maleinsäureanhydrid zu Dimethylmaleinsäureanhydrid unter Einfluss von 2-Aminopyridin". Helvetica Chimica Acta. 67 (7): 1897–1905. doi:10.1002/hlca.19840670728.

[6] Hood DK (2024). "Maleic Anhydride, Maleic Acid, and Fumaric Acid". Kirk-Othmer Encyclopedia of Chemical Technology. pp. 1–51. doi:10.1002/0471238961.1301120506051220.a01.pub3. ISBN 978-0-471-48494-3.

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