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Enzyme-triggered and self-cleaving fragrant alcohol precursors
Felix Flachsmann1, Markus Gautschi, Jean-Pierre Bachmann
1Fragrance Research, Givaudan Schweiz AG, Uberlandstrasse 138, CH-8600 Dübendorf. felix.flachsmann@givaudan.com
Chemistry & Biodiversity
|July 12, 2008
Summary
Fragrance precursors enhance scent longevity in personal care products. Novel oligocarbonates offer enzyme-independent, long-lasting release of fragrant alcohols, improving product performance.
Area of Science:
- Organic Chemistry
- Materials Science
- Fragrance Chemistry
Background:
- High volatility and water solubility of natural perfumery alcohols limit their effectiveness in fabric and personal care.
- Fragrance precursors offer a solution for controlled scent release, enhancing substantivity.
Purpose of the Study:
- To develop and evaluate novel fragrance precursors for improved scent longevity.
- To investigate multi-odorant precursors and enzyme-independent oligocarbonates for controlled fragrance release.
Main Methods:
- Synthesis of multi-odorant precursors (esters and carbonates) and oligocarbonates of fragrant alcohols.
- Enzymatic cleavage studies for precursor activation.
- Analysis of fragrance release kinetics, including enzyme-independent mechanisms.
Main Results:
- Multi-odorant precursors release fragrant ketones, lactones, and alcohols upon enzymatic cleavage.
- Gluconolactone oligocarbonate 27 demonstrates outstanding enzyme-independent performance for sustained release of (Z)-hex-3-en-1-ol.
- Polyfunctional compounds exhibit complex rearrangements and intramolecular reactions influencing release kinetics.
Conclusions:
- Fragrance precursors significantly enhance the substantivity of volatile perfumery alcohols.
- Oligocarbonates represent a promising class of enzyme-independent controlled-release systems for fragrances.
- Understanding the complex reaction pathways is key to optimizing fragrance delivery systems.
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