(Z,Z,E)-7,11,13-Hexadecatrienal Synthesis via Wittig Reaction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for preparing the sex pheromone (Z,Z,E)-7,11,13-hexadecatrienal, used to control the citrus leafminer pest, rely on oxidation reactions that pose risks of explosion and struggle with high-purity and high-yield isolation, especially at an industrial scale.
Innovation Solution
The method involves synthesizing (Z,Z,E)-1-chloro-6,10,12-pentadecatriene and converting it into a Grignard reagent for a coupling reaction with ethyl orthoformate, followed by hydrolysis, eliminating the need for oxidation reactions and enabling high-purity and high-yield production of (Z,Z,E)-7,11,13-hexadecatrienal.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If oxidation reaction is used to prepare (Z,Z,E)-7,11,13-hexadecatrienal, then the sex pheromone substance can be synthesized, but the risk of explosion increases and the isolation of high-purity product becomes difficult
Solution Approach 1:
The patent extracts and removes the oxidation step from the synthesis pathway. Instead of using oxidation reactions (which pose explosion risks), the invention employs a Wittig reaction followed by deprotection of acetal groups to generate the aldehyde functionality, thereby eliminating the harmful oxidation step while still achieving the desired sex pheromone product
Solution Approach 2:
The patent introduces an acetal-protected intermediate compound as a mediator in the synthesis pathway. The Wittig reaction produces an acetal-protected aldehyde, which then undergoes controlled deprotection to yield the final aldehyde product. This intermediary approach avoids direct oxidation and its associated safety hazards
2Manufacturing precision
If oxidation reaction is used to prepare (Z,Z,E)-7,11,13-hexadecatrienal, then the synthesis can proceed, but the yield and purity of the isolated product are insufficient
Solution Approach 1:
By removing the oxidation step from the synthesis pathway, the patent eliminates the side reactions and over-oxidation problems that typically plague oxidation-based methods. This results in cleaner reaction mixtures that are easier to purify and yield higher amounts of the desired aldehyde product
Solution Approach 2:
The patent uses a Wittig reaction to construct the carbon-carbon double bonds with precise stereochemical control, creating the correct (Z,Z,E) configuration directly. This approach copies the desired molecular architecture more accurately than oxidation methods, which often require subsequent purification to remove isomeric byproducts
3Ease of manufacture
If oxidation reaction is used for industrial-scale production, then synthesis can be performed, but the process becomes unsuitable for mass production
Solution Approach 1:
By extracting the oxidation step from the synthesis pathway, the patent eliminates a major barrier to industrial scaling. The Wittig reaction and acetal deprotection are more amenable to large-scale continuous processing, with better safety profiles and easier product isolation, making the overall process suitable for mass production of the sex pheromone
Solution Approach 2:
The patent changes the chemical parameters of the synthesis pathway by replacing oxidation reactions with Wittig olefination and acetal deprotection. These parameter changes result in reactions that are more controllable at industrial scales, with fewer safety concerns and better product recovery efficiency
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
This approach allows for the mass production of (Z,Z,E)-7,11,13-hexadecatrienal at a low cost with high reliability and efficiency, avoiding the risks associated with oxidation reactions and ensuring high purity and yield.
Implementation Method 1
converting the (Z,Z,E)-1-chloro-6,10,12-pentadecatriene into a corresponding Grignard reagent, conducting a coupling reaction between the Grignard reagent and ethyl orthoformate
Implementation Method 2
conducting a hydrolysis treatment, leading to the completion of the invention
Data Source
AI summary
Provided are (Z,Z,E)-1-chloro-6,10,12-pentadecatriene that can be synthesized without an oxidation reaction and a method for preparing (Z,Z,E)-7,11,13-hexadecatienal by using (Z,Z,E)-1-chloro-6,10,12-pentadecatriene while not using an oxidation reaction. More specifically, provided is a method for preparing (Z,Z,E)-7,11,13-hexadecatrienal including a step of reacting a Grignard reagent into which (Z,Z,E)-1-chloro-6,10,12-pentadecatriene is converted with ethyl orthoformate to obtain (Z,Z,E)-1,1-diethoxy-7,11,13-hexadecatriene, and a step of treating the (Z,Z,E)-1,1-diethoxy-7,11,13-hexadecatriene with an acid to obtain (Z,Z,E)-7,11,13-hexadecatrienal.