5-FORMYLISOXAZOLE

5-FORMYLISOXAZOLE Property

Boiling point:

212℃

Density 

1.258

Flash point:

82℃

storage temp. 

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

pka

-3.78±0.50(Predicted)

Appearance

White to off-white Solid

Safety

Risk Statements 

43

Safety Statements 

36/37

HS Code 

2934999090

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Warning

Hazard statements

H302Harmful if swallowed

Precautionary statements

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-FORMYLISOXAZOLE Chemical Properties,Usage,Production

Uses

5-Isoxazolecarbaldehyde is the derivative of 5-Isoxazolecarboxylic Acid, which is used as a reagent in the synthesis of N-(benzo[1,2,3]triazol-1-yl)-N-((benzyl)acetamido)phenyl carboxamides as severe acute respiratory syndrome coronavirus (SARS-CoV) 3CLpro inhibitors. 5-Isoxazolecarboxylic Acid is also used as a reagent in the synthesis of TC-6683, a α4β2 nicotinic acetylcholine receptor agonist for treatment of cognitive disorders.

Synthesis

Step 2: Synthesis of isoxazole-5-carbaldehyde In a round bottom flask, isoxazol-5-yl-methanol (511 mg, 5.16 mmol) was dissolved in dichloromethane (30 mL). Dess-Martin periodate (2.3 g, 5.41 mmol) was added and the reaction mixture was stirred for 1.5 h at room temperature. Upon termination of the reaction, 50 mL of 10% aqueous Na2S2O3 and saturated aqueous NaHCO3 were added, followed by extraction with dichloromethane (2 x 30 mL). The organic layer was washed sequentially with saturated NaHCO3 aqueous solution, water and brine. The aqueous layer was back-extracted with dichloromethane. The organic layers were combined, dried over anhydrous sodium sulfate, filtered and concentrated. The residue was purified by silica gel column chromatography using EtOAc/hexane (gradient 0-40% EtOAc) as eluent to afford 226 mg (45% yield) of isoxazole-5-carbaldehyde as a colorless oil.1H NMR (CDCl3, 300 MHz) δ (ppm): 10.05 (s, 1H), 8.44 (d, J = 1.9 Hz, 1H). 7.02 (d, J = 1.9 Hz, 1H).

References

[1] Patent: WO2013/30138, 2013, A1. Location in patent: Page/Page column 154
[2] Tetrahedron, 1967, vol. 23, p. 4697 - 4707