• Adds leather backbone to compositions
• Brings vintage chypre & fougère green sharpness
• Provides a dry, bitter counterbalance to florals and musks
• Functions as a fixative (long-lasting and dominant)
  
  

Isobutyl Quinoline (IBQ) is a legendary perfumery ingredient known for its intensely powerful leather and green character. First used in the early 20th century, IBQ quickly became a cornerstone of chypre, fougère, and leather fragrances, giving them their unmistakable dry, bitter-green, mossy-leather backbone.

• IUPAC Name: 5,6,7,8-Tetrahydro-2-isobutylquinoline
  
• CAS Number: 65442-31-1 (sometimes older variants listed as 93-19-6 depending on isomer)
  
• Molecular Formula: C13H19N
  
• Appearance: Yellow to brownish liquid
  
• Odor Description:
  Intense leathery, green, slightly earthy, and bitter note
  Reminiscent of leather, quinoline, tobacco, ink, and moss
  Very powerful even in trace amounts

Leather Accords – Essential for creating dry, smoky, animalic leather effects in fine fragrances.

Chypre & Fougère – Enhances the green, mossy backbone of these classical perfume families.

Niche & Vintage Perfumes – Brings an old-school sophistication reminiscent of early 20th-century French perfumery.

Tobacco & Woody Blends – Adds a bitter-green edge that complements vetiver, cedarwood, oakmoss, and tobacco notes.

Contrast in Florals – In ultra-low doses, provides a dark counterpoint to white florals (jasmine, tuberose) and musks.

💡 Many perfumers also pair IBQ with oakmoss, labdanum, and castoreum replacers to recreate that classic vintage leather accord in a controlled, modern-safe way.

Q1. What does Isobutyl Quinoline smell like?

A: It has an intense leather-green aroma with notes of oakmoss, tobacco, and earthy soil. Very sharp, bitter, and long-lasting — often described as “vintage leather perfume in a bottle.”

Q2. What is Isobutyl Quinoline used for in perfumery?

A: Mainly in leather accords, chypres, and fougères. It gives perfumes a dark, bitter-green backbone and adds depth to woody, mossy, and tobacco blends.

Q3. How strong is it?

A: Extremely strong! It should be used in trace amounts (<0.1%) of the finished fragrance. Overuse can overwhelm the entire composition.

Q4. Can it be blended with florals?

A: Yes — in tiny amounts it creates a contrasting effect with white florals like jasmine, tuberose, and ylang-ylang, making them richer and more complex.

Q5. Is Isobutyl Quinoline safe?

A: It is IFRA-restricted in some product categories due to sensitization risks. Always check the latest IFRA guidelines before use.

Q6. What form does it come in?

A: Usually a yellow to brownish liquid, soluble in alcohol, oils, and DPG (Dipropylene Glycol).

Q7. Is it beginner-friendly?

A: Only with caution — beginners should always pre-dilute (1% or less) before experimenting. It’s easy to overdose, so small-scale trials are recommended.