Glyceric Acid Ester Production via TEMPO Catalysis
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for producing glyceric acid esters with protected hydroxy groups at the 2- and 3-positions as cyclic acetal groups result in low yields and high economic and workload disadvantages due to high water-solubility of the desired compounds, making industrialization challenging.
Innovation Solution
A novel method involving oxidative esterification of a compound represented by formula (I) to produce a glyceric acid ester (II) with specific R groups, optimizing reaction conditions to achieve high yield and efficient recovery in the water-washing step, using a nitroxyl radical method with TEMPO and TCCA as catalysts, and employing acetalization of glycerol with acid catalysts.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If conventional oxidation methods are used to produce glyceric acid ester, then the reaction can proceed, but the yield is low and the production cost is high
Solution Approach 1:
The patent changes the reaction parameters by using TEMPO catalyst with specific structure (formula VIII) and controlling the oxidation conditions (oxidizing agent type, temperature, solvent) to achieve high yield of glyceric acid ester. The specific parameter optimization includes using 0.01-1 mol% TEMPO relative to substrate, maintaining reaction temperature at -78°C to 25°C, and selecting appropriate oxidizing agents like TCCA or NaClO, which collectively resolve the contradiction between productivity and manufacturing ease.
Solution Approach 2:
The patent introduces TEMPO as an intermediary catalyst that mediates the oxidation reaction between the substrate (compound I) and the oxidizing agent. TEMPO acts as a mediator that facilitates electron transfer and enables the reaction to proceed under milder conditions with higher efficiency, thereby improving yield while reducing production cost compared to conventional direct oxidation methods.
2Ease of operation
If the desired compound has high water-solubility, then it can be easily handled, but the recovery in water-washing step is low and workload increases
Solution Approach 1:
The patent applies local quality modification by introducing specific hydrophobic groups (R1 groups in formula II) at specific positions of the glyceric acid ester molecule. This creates a molecule with differential solubility characteristics - the acetal group provides water solubility for handling, while the hydrophobic R1 groups ensure low water solubility for easy recovery. This local differentiation resolves the contradiction between ease of operation and productivity in the water-washing step.
3Speed
If conventional catalysts are used for oxidation, then the reaction can proceed, but the reaction efficiency is low and requires harsh conditions
Solution Approach 1:
The patent replaces conventional mechanical/thermal oxidation methods with a catalytic chemical system using TEMPO. Instead of relying on harsh physical conditions (high temperature, strong oxidizing agents), the invention uses a chemical catalyst (TEMPO with oxoammonium cation) to lower the activation energy and enable the reaction to proceed under milder conditions with higher efficiency. This substitution of mechanical/thermal energy with chemical catalysis resolves the contradiction between reaction speed and temperature requirements.
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 method achieves a high yield of glyceric acid ester with improved recovery in the water-washing step, reducing the workload and economic burden, and providing a stable acetal group, suitable for various applications as a synthetic intermediate.
Implementation Method 1
a step of oxidatively esterifying a compound represented by the following formula (I)
Implementation Method 2
using a nitroxyl radical method with TEMPO and TCCA as catalysts
Implementation Method 3
employing acetalization of glycerol with acid catalysts
Implementation Method 4
acetalization of glycerol with acid catalysts
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The present invention relates to providing a novel glyceric acid ester which can be produced in a high yield and is expected to be applied as a synthetic intermediate, and a method of producing the same. In addition, the present invention relates to providing a novel glyceric acid ester which exhibits a high recovery in a water-washing step after the reaction and a small work load at the time of production, and is expected to be applied as a synthetic intermediate, and a method of producing the same. The present invention provides a method of producing a compound represented by the following formula (II), including a step of oxidatively esterifying a compound represented by the following formula (I): wherein, in the formulae (I) and (II), R1 and R2 each independently represent a hydrogen atom or a monovalent hydrocarbon group, or R1 and R2 are bonded to each other to form a divalent hydrocarbon group for constituting a ring structure, provided that the case where R1 and R2 are a methyl group at the same time is excluded.