Odorous Acetals of Ethyl Vanillin for Fragrance Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current 2-alkoxyphenols used in perfumery for vanilla notes face challenges such as instability in alkali media, discoloration, and the generation of unpleasant off-notes, along with high waste production during ester formation, limiting their performance and environmental sustainability.
Innovation Solution
Development of novel acetal compounds derived from reacting phenols with ethoxyethene using Brønsted acid as a catalyst, which provide enhanced stability, substantivity, and a clear vanilla-like character while reducing waste, and modifying the odor profile with improved air- and photo-stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If esters are formed by reacting phenols with carboxylic acids or alkylcarbonate esters, then the hydroxyl group is protected and oxidation is retarded, but significant amount of waste is generated
Solution Approach 1:
The patent changes the chemical parameters of the protecting group from traditional esters (carboxylic acid derivatives) to acetals (aldehyde derivatives). This parameter change in the protecting group type enables 100% atom economy by reacting phenols with ethoxyethene, eliminating waste generation while maintaining the protective function against oxidation and discoloration.
Solution Approach 2:
The patent converts the previously harmful waste generation into a beneficial feature by using acetal protection that achieves 100% atom economy. The reaction of phenols with ethoxyethene produces no byproducts, transforming the waste problem into an environmentally friendly process advantage.
2Reliability
If the hydroxyl group is protected to prevent discoloration and oxidation, then air-stability is improved, but odor intensity decreases and off-notes may appear
Solution Approach 1:
The patent changes the protecting group parameter from traditional esters to acetals, which have different chemical properties. The acetal group provides stability against oxidation and discoloration while being odorless and not prone to hydrolysis, thus maintaining the desired odor profile without generating off-notes like rancid or acidic sensations.
Solution Approach 2:
The acetal group acts as an intermediary protecting group that temporarily masks the hydroxyl group during storage and processing, preventing oxidation and discoloration. It can be easily removed or remains stable depending on conditions, providing control over the phenolic functionality while maintaining odor quality.
3Reliability
If traditional protecting groups are used, then oxidation is retarded, but unpleasant off-notes are generated upon hydrolysis
Solution Approach 1:
The patent converts the potential harm of hydrolysis-induced off-notes into a benefit by using acetals that are resistant to hydrolysis under normal conditions. The acetal group remains stable in aqueous and alcoholic environments, preventing the formation of rancid or acidic off-notes that would result from ester hydrolysis, while still providing oxidation protection.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The new acetal compounds exhibit greater substantivity and persistence, retaining the parent phenol's odor while offering improved stability and reduced waste generation, making them suitable for a wide range of fragrance applications with a natural vanilla and spicy impression.
Implementation Method 1
reacting phenols with ethoxyethene using Brønsted acid as a catalyst
Data Source
AI summary
The present invention relates to new odorous acetals which are useful as fragrance or flavor materials in particular in providing vanilla and spicy notes with a natural impression resembling vanilla absolute.