5,6,7,8-Tetrahydro-[1,2,4]triazolo[1,5-a]pyrazine

5,6,7,8-Tetrahydro-[1,2,4]triazolo[1,5-a]pyrazine Property

Boiling point:

319.8±52.0 °C(Predicted)

Density 

1.53±0.1 g/cm3(Predicted)

storage temp. 

under inert gas (nitrogen or Argon) at 2–8 °C

pka

6.05±0.20(Predicted)

Appearance

White to light brown Solid

Safety

HS Code 

2933998090

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Warning

Hazard statements

H302Harmful if swallowed

H315Causes skin irritation

H319Causes serious eye irritation

H332Harmful if inhaled

H335May cause respiratory irritation

Precautionary statements

P261Avoid breathing dust/fume/gas/mist/vapours/spray.

P280Wear protective gloves/protective clothing/eye protection/face protection.

P305+P351+P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.

5,6,7,8-Tetrahydro-[1,2,4]triazolo[1,5-a]pyrazine Chemical Properties,Usage,Production

Synthesis

Platinum(IV) oxide (2.75 g, 12.1 mmol) was added to a suspension of 2-methoxyethanol (150 mL) containing calcium oxide (9.30 g, 166 mmol) and [1,2,4]triazolo[1,5-a]pyrazine (18.10 g, 151 mmol) under nitrogen protection. The reaction mixture was stirred under hydrogen atmosphere for 21.5 h before being filtered through diatomaceous earth and washed with a solvent mixture of dichloromethane/ethanol (9:1). The filtrate was concentrated, co-evaporated with toluene and diisopropyl ether, subsequently dissolved in ethyl acetate, filtered again through diatomaceous earth and washed with ethyl acetate, after which it was concentrated again. The resulting residue was dissolved in hot diisopropyl ether, filtered, washed with diisopropyl ether and finally concentrated under vacuum for 7 hours. The product 5,6,7,8-tetrahydro-[1,2,4]triazolo[1,5-A]pyrazine was obtained in a yield of 17.12 g (92% yield).

References

[1] Patent: US2008/153843, 2008, A1. Location in patent: Page/Page column 68
[2] Journal of Medicinal Chemistry, 2014, vol. 57, # 9, p. 3687 - 3706
[3] Patent: WO2006/9886, 2006, A1. Location in patent: Page/Page column 46
[4] Bioorganic and Medicinal Chemistry Letters, 2007, vol. 17, # 21, p. 5934 - 5939
[5] Patent: WO2009/90055, 2009, A1. Location in patent: Page/Page column 108; 109