2-Aminopyridine

2-Aminopyridine
Names
Preferred IUPAC name
Pyridin-2-amine
Other names
2-Pyridinamine; 2-Pyridylamine; α-Aminopyridine; α-Pyridylamine
Identifiers
3D model (JSmol)
ChEMBL
ChemSpider
ECHA InfoCard 100.007.263 Edit this at Wikidata
EC Number
  • 207-988-4
RTECS number
  • US1575000
UNII
UN number 2671
  • InChI=1S/C5H6N2/c6-5-3-1-2-4-7-5/h1-4H,(H2,6,7) checkY
    Key: ICSNLGPSRYBMBD-UHFFFAOYSA-N checkY
  • InChI=1/C5H6N2/c6-5-3-1-2-4-7-5/h1-4H,(H2,6,7)
    Key: ICSNLGPSRYBMBD-UHFFFAOYAM
  • n1ccccc1N
  • c1ccnc(c1)N
Properties
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)
>100%
Hazards
GHS labelling:
GHS06: ToxicGHS07: Exclamation markGHS09: Environmental hazard
Danger
H301, H311, H312, H315, H319, H335, H411
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):
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).
checkY verify (what is checkYX markN ?)

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. It is produced by the reaction of sodium amide with pyridine, the Chichibabin reaction.

Reactions

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

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.

Toxicity

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

References

  1. 1 2 3 4 5 "#0026". NIOSH Pocket Guide to Chemical Hazards. National Institute for Occupational Safety and Health.
  2. ↑ "2-Aminopyridine". Immediately Dangerous to Life or Health Concentrations. National Institute for Occupational Safety and Health.
  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.
  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.
  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.