This product(s) resides on a APICMO contract.
We have the ability to produce, synthesize and manufacture large quantities of 4-Chloro-7-azaindole(55052-28-3) with quality control system under CGMP manufacturing regulations.



4-Chloro-7-azaindole (55052-28-3) Specifications

CAS 55052-28-3
CAS Min % 95%
CAS Max % 100%
MDL Number MFCD08272232
Chemical Name or Material 4-Chloro-7-azaindole
Infrared Spectrum Authentic
Physical Form Powder or Chunks
Packaging Glass bottle
Molecular Formula C7H5ClN2
Molecular Weight (g/mol) 152.581
Color Pale Yellow-Greyish Yellow
Melting Point 176° to 181°C
Assay 98%

At APICMO, we synthesize and manufacture large amounts of 4-Chloro-7-azaindole, as per the CGMP quality control regulations. This product falls in the same category as heterocycles, azaindoles, indole derivatives, and the related building blocks.

4-Chloro-7-azaindole (55052-28-3) Description

In the crystal structure analysis of 4-Chloro-7-azaindole, we found out that there’s formation of a centrosymmetric dimer, which is connected by two N-H···N hydrogen bonds. The bonding occurs between the pyridine and pyrrole rings. The C2-H2···Br hydrogen bonds will stabilize the structure.

In this analysis, the Infrared and Raman spectra are recorded while in a solid state. The theoretical calculations are performed with the B3LYP method.

Chemical structure of 4-Chloro-7-azaindole


4-Chloro-7-azaindole (55052-28-3) Product specifications

Chemical name 4-Chloro-7-azaindole
IUPAC name 4-Chloro-1H-pyrrolo[2,3-b]pyridine
CAS no. 55052-28-3
Molecular formula C7H5ClN2
Molecular weight (g/mol) 152.581
Monoisotopic mass (g/mol) 152.014
Structural formula 4-Chloro-7-azaindole powder (55052-28-3)
Density (g/cm3) 1.425
Melting point (˚C) 176 – 181
Physical state Solid
Purity 98% pure
Synonyms · 4-Chloro-1H-pyrrolo[2,3-b]pyridine

· 1H-pyrrolo[2,3-b]pyridine, 4-Chloro

· 4-Chloropyrrolo[2,3-b]pyridine

Chemical and Physical Properties of 4-Chloro-7-azaindole

4-Chloro-7-azaindole (55052-28-3) Appearance

4-Chloro-7-azaindole is a pale yellow solid existing in powder form, crystals, or solid chunks.

(55052-28-3) Bonding

Hydrogen bond Donor count – 1 unit

Acceptor count – 1 unit

Covalent 1
Rotatable bond 0


This chemical is slightly soluble in water, chloroform, and methanol.

4-Chloro-7-azaindole (55052-28-3) Computed Properties

Property Name Property value
Exact Mass (g/mol) 152.014
Isotope Atom Count 0
Undefined Atom Stereocenter Count 0
Defined Atom Stereocenter Count 0
Defined Bond Stereocenter Count 0
Undefined Bond Stereocenter Count 0
Heavy Atom Count 10
Formal Charge 0
Compound is Canonicalized Yes
Complexity 129
XLogP3-AA 1.9
Refractive index 1.703
Topological polar surface area 28.7A^2

4-Chloro-7-azaindole (55052-28-3) Synthesis Route

There are up to 8 routes of synthesizing this product. Below is the listing in the order of the most to the least recommended method:


Uses of 4-Chloro-7-azaindole

  • Pharmaceutical intermediate for drug research and discoveries

Hazards Associated with 4-Chloro-7-azaindole

  • Severe eye irritation, which might lead to permanent damage
  • Poisonous if swallowed or ingested, leading to acute toxicity, sore mouth, unconsciousness, blurry vision, and other severe symptoms
  • Causes skin irritation, redness, and corrosions
  • Leads to respiratory irritation, short breath, or nausea

Safety measures when dealing with 4-Chloro-7-azaindole

Personal Protection

To minimize the adverse effects exhibited by 4-Chloro-7-azaindole, wear appropriate protective equipment. For face protection, use a dust mask, eye shields, and an air-purifying respirator. Put on impervious gloves and rubber gloves for your hand and feet safety.

1. 4-Chloro-7-azaindole (55052-28-3) Engineering Controls

Work in a laboratory, which is well-equipped with exhaust ventilation, emission source isolation, and an air cleaning device, and a fume hood. An emergency safety shower and eyewash equipment come in hand for timely first aid administration.

2. 4-Chloro-7-azaindole (55052-28-3) First Aid Measures

  • Eye contact

If you have contact lenses, remove them before flushing the eyes with copious amount of running water for 10 minutes. Seek medical attention if irritation persists.

  • Ingestion

Do not induce vomiting but rather drink plenty of water. Consult a poison centre immediately or seek further medical care.

  • Inhalation

Move the casualty to fresh air or a well-ventilated room. Administer oxygen support in case of breathing difficulties and seek the attention of a medic.

  • Skin contact

Take off the contaminated clothing as soon as possible. Thoroughly wash the area with enough running water and mild soap for about 15 minutes. If redness, soreness, corrosion, or irritation persists, seek medical attention.

3. Safety Measures When Using 4-Chloro-7-azaindole

When the product is in use, take note of the following measures:

  • Avoid inhaling fumes, dust, vapours, gas, dust, or any other emissions
  • Wear a full suit including chemical-resistant gloves, rubber footwear, and face protection
  • Work in a fume hood
  • Operate from a well-ventilated room or outdoor space

4. After Use

After using 4-Chloro-7-azaindole, observe the points below:

  • Dispose of the residues and empty containers as per the local or federal regulations
  • Store any remnants in the original package and tightly seal it
  • Do not allow any spills to flow along the water channels or drainages
  • Wash the working bench thoroughly and ventilate it
  • Wash hands thoroughly
  • Wash the contaminated clothing

5. When out of Use

When not in use, consider the following:

  • Keep the product locked in its original container
  • Store under low temperatures, preferably in a refrigerator at 0 – 8˚C

6. 4-Chloro-7-azaindole (55052-28-3) Storage and Handling


  • Keep the chemical in a tightly closed container
  • Lock it up in a secure place to prevent unauthorized access
  • For long-term storage, store within room temperature


  • Wear protective clothing to limit hazard exposure
  • Do not breathe the emissions or air contaminants
  • Work under close supervision of a professional

7. 4-Chloro-7-azaindole (55052-28-3) Accidental Measures


Never allow the spills to flow along the normal drainage. If in a solid state, scoop the chunks and toss them in a labelled waste container. For liquid spills, use an absorbent to pick up the chemicals and eliminate them according to the local regulations.

Fire control

Put out the flame using dry chemical powder, carbon dioxide, or foam depending on the causative agent. Make sure to wear protective gears to shield against toxic combustion products like hydrogen chloride, nitrogen oxides, carbon monoxide, or carbon dioxide.

8. Stability and Reactivity

4-Chloro-7-azaindole is stable under normal storage conditions. Avoid subjecting it under heat, moisture, strong acids, or oxidizing agents since it might trigger chemical decomposition.

9. Chemical Disposal

Dispose of 4-Chloro-7-azaindole as a special waste according to the local, federal, and the state’s chemical waste disposal regulations.

10. 4-Chloro-7-azaindole (55052-28-3) Shipping Info

There are no known hazards associated with either ground or air transportation.

 (55052-28-3) Regulatory Info

The packaging, maximum quantity and the threshold level of 4-Chloro-7-azaindole comply with the chemical quality control system. Be sure to follow the guidelines given by your local or federal regulatory bodies.

4-Chloro-7-azaindole Technical Service

We pride in a team of dedicated scientists with experience in chemical analysis, research, life and material science, and chromatography.

4-Chloro-7-azaindole Bulk Order and Pricing

If you require large quantities of 4-Chloro-7-azaindole for research, development, or chemical synthesis, feel free to place your order with us.


  1. Cornell University, Journal of Organic Chemistry of the USSR. – Volume 8 – Page 2469.
  2. Wieslaw M. Kazmierski , Antiviral Drugs: From Basic Discovery Through Clinical Trials page 10-27.
  3. John A. Joule, Keith Mills,  Heterocyclic Chemistry, Page 5-10.
  4. National Centre For Biotechnology Information, US. National Library Of Medicine, Pubchem,4-Chloro-7-azaindole , Sections 1-9.