4-Bromo-5-chloro-1H-pyrrolo[2,3-b]pyridine

4-Bromo-5-chloro-1H-pyrrolo[2,3-b]pyridine Property

Density 

1.878

storage temp. 

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

pka

12.04±0.40(Predicted)

Appearance

Off-white to pink Solid

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Warning

Hazard statements

H315Causes skin irritation

H319Causes serious eye irritation

H335May cause respiratory irritation

Precautionary statements

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

P264Wash hands thoroughly after handling.

P264Wash skin thouroughly after handling.

P271Use only outdoors or in a well-ventilated area.

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

P302+P352IF ON SKIN: wash with plenty of soap and water.

P304+P340IF INHALED: Remove victim to fresh air and Keep at rest in a position comfortable for breathing.

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

P312Call a POISON CENTER or doctor/physician if you feel unwell.

P321Specific treatment (see … on this label).

P332+P313IF SKIN irritation occurs: Get medical advice/attention.

P337+P313IF eye irritation persists: Get medical advice/attention.

P362Take off contaminated clothing and wash before reuse.

P403+P233Store in a well-ventilated place. Keep container tightly closed.

P405Store locked up.

P501Dispose of contents/container to..…

4-Bromo-5-chloro-1H-pyrrolo[2,3-b]pyridine Chemical Properties,Usage,Production

Uses

4-Bromo-5-chloro-1H-pyrrolo[2,3-b]pyridine can be used in drug synthesis and as a pharmaceutical intermediate in scientific research.

Synthesis

5-Chloro-1H-pyrrolo[2,3-b]pyridine-7-oxide (5.00 g, 29.66 mmol) was used as a raw material, which was dissolved with tetrabutylammonium bromide (Bu4Br, 19.12 g, 59.31 mmol) in N,N-dimethylformamide (DMF, 200 mL). Trifluoromethanesulfonic anhydride (Tf2O, 20.91 g, 74.20 mmol) was slowly added dropwise to the above solution at 0 °C. After the dropwise addition, the reaction mixture was stirred at room temperature for 2 hours. Subsequently, the reaction solution was poured into water (500 mL), and the pH of the mixture was adjusted to 8-9 with saturated aqueous sodium bicarbonate (NaHCO3). The precipitate was collected by filtration, and the filter cake was washed with water (50 mL x 3) and dried under vacuum at 60 °C overnight to afford 4-bromo-5-chloro-1H-pyrrolo[2,3-b]pyridine as an off-white solid (5.83 g, yield 84.9%). Mass spectrum (ESI, positive ion mode) m/z: 231.0 [M + H]+; NMR hydrogen spectrum (400 MHz, DMSO-d6) δ (ppm): 12.24 (s, 1H), 8.30 (s, 1H), 7.68 (s, 1H), 6.45 (s, 1H).

References

[1] Patent: WO2018/169700, 2018, A1. Location in patent: Paragraph 00328; 00329
[2] Patent: US2010/81645, 2010, A1. Location in patent: Page/Page column 37
[3] Patent: WO2006/127587, 2006, A1. Location in patent: Page/Page column 87