Flavors & Fragrances
REACH
Indole
CAS Number
120-72-9
EC Number
204-420-7
FEMA Number
FEMA 2593
What is Indole?
Indole (CAS 120-72-9), also known as 2,3-Benzopyrrole, is a naturally occurring heterocyclic compound sourced from coal tar or produced synthetically. FEMA 2593.
Where is Indole used?
- Fine fragrance and personal care: anchors jasmine, tuberose and white floral accords
- Flavor systems: trace levels in coffee, tobacco and fruit for complexity
- Printing and packaging: intermediate for dyes and pigments, particularly indigo-related colorants
- Research and specialty chemicals: building block for pharmaceutical intermediates and agrochemical synthesis
- At low concentrations it delivers a floral, jasmine-like character.
Good to know: At higher concentrations it contributes animalic, fecal notes. Standard commercial grades include technical and fragrance/flavor-grade material.
Commercial specifications
- Purity typically 98% to 99%+ for flavor and fragrance applications
- Packaging from small drums to bulk quantities
Other Names (Synonyms)
indol|1H-Indole|2,3-Benzopyrrole|1-Benzazole|Ketole|1-Azaindene
What are the physical properties of Indole?
Melting Point 52 °C
Boiling Point 128-133 °C @ Press: 28 Torr
Density 1 x 10<sup>-6</sup> g/cm³ @ Temp: 25 °C
Flash Point >230 °F
Appearance white crystals with an unpleasant odour
Color White to slightly pink
Odor fecal odor, floral in high dilution
Form Crystalline Powder
Water Solubility 2.80 g/L (25 ºC)
Vapor Pressure 0.016 hPa (25 °C)
Refractive Index 1.6300
pH 5.9 (1000g/l, H2O, 20℃)
Log P 2.14-2.24
How is Indole classified and handled safely? Learn More
Danger
GHS05· Corrosive GHS06· Toxic GHS07· Irritant GHS09· Environmental Hazard
Hazard Statements
H302 Harmful if swallowed
H311 Toxic in contact with skin
H318 Causes serious eye damage
H319 Causes serious eye irritation
Precautionary Statements
P262 Do not get in eyes, on skin, or on clothing.
P264 Wash … thoroughly after handling.
P270 Do not eat, drink or smoke when using this product.
P280 Wear protective gloves/protective clothing/eye protection/face protection.
Which trade and regulatory codes apply to Indole?
HS Code 29339900
UN Number 2811
ADR Class 6.1
Packing Group III
Storage Class 6.1C - Combustible acute toxic Cat.3
toxic compounds or compounds which causing chronic effects
WGK (Germany) 1