Selective Dehydrogenation of Vitamin A Intermediates for Higher Yield
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for producing vitamin A intermediates like dihydroretinal and dihydroretinyl alkanoate suffer from low yields and difficulty in converting the resulting carboxylic ester into vitamin A acetate.
Innovation Solution
A dehydrogenation process using specific oxidative reactants, such as compounds of formula (III), in the presence of additives like pyridine or triethoxyamine, and solvents like benzene or toluene, at elevated temperatures, selectively transforms compounds of formula (I) into compounds of formula (II), which are intermediates in vitamin A synthesis.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If conventional dehydrogenation methods are used to produce dihydroretinal or dihydroretinyl alkanoate, then the synthesis can be performed, but the yield is low (31%) and the carboxylic ester is difficult to convert into vitamin A acetate
Solution Approach 1:
The patent changes the chemical parameters of the dehydrogenation process by introducing specific oxidative reactants (formula III with electron-withdrawing groups) and controlling reaction conditions (temperature, solvent, additives) to achieve high yield (70-85%) and improve convertibility of the product into vitamin A acetate
Solution Approach 2:
The patent uses specific oxidative reactants as intermediaries to facilitate the dehydrogenation reaction. These oxidative reactants (such as those with -CN, -Cl, or -F groups) act as mediators that enable the transformation of formula (I) to formula (II) with improved yield and convertibility, solving the problem of low yield and difficulty in conversion
2Productivity
If existing dehydrogenation processes are used, then the synthesis pathway can be established, but the process is complex and requires multiple steps
Solution Approach 1:
The patent extracts and eliminates unnecessary intermediate steps from the conventional synthesis pathway. By using a direct dehydrogenation approach with specific oxidative reactants, the process reduces the number of steps required to produce vitamin A acetate from dihydroretinal or dihydroretinyl alkanoate, thereby simplifying the overall synthesis process while maintaining high 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 process enhances the yield and facilitates the conversion of intermediates into vitamin A derivatives, providing a more efficient synthesis pathway.
Implementation Method 1
The dehydrogenation is carried out in the presence of at least one oxidative reactant of formula (III)... This process enhances the yield and facilitates the conversion of intermediates into vitamin A derivatives
Data Source
AI summary
The present invention relates to a new dehydrogenation process of specific compounds.