Synthesis of 9,9-Bis(hydroxymethyl)fluorene via Reduced DMSO
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for synthesizing 9,9-bis(hydroxymethyl)fluorene and subsequent 9,9-bis(methoxymethyl)fluorene require large volumes of dimethyl sulfoxide (DMSO), leading to increased costs and environmental concerns due to the need for extensive solvent recovery and purification processes, and result in partial decomposition of DMSO, reducing yield and purity.
Innovation Solution
A process involving a mixture of paraformaldehyde, dimethylsulfoxide, and toluene with sodium alkoxide, where fluorene is added as a solid, allowing for reduced DMSO usage and eliminating the need for separate purification steps, and subsequent etherification using dimethyl sulfate in multiple portions to maintain reaction stability and yield.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If large volumes of DMSO are used in the hydroxymethylation reaction, then the reaction proceeds effectively, but the solvent recovery becomes difficult and costs increase
Solution Approach 1:
The patent extracts DMSO from the reaction mixture through aqueous workup, separating it from the organic phase containing the product. This allows DMSO to be removed and recovered separately, resolving the contradiction between maintaining reaction effectiveness with high DMSO volumes and enabling solvent recovery.
Solution Approach 2:
The patent implements a process where DMSO is discarded from the organic phase during extraction and then recovered from the aqueous phase through evaporation or distillation. This two-stage recovery approach addresses both the need for effective reaction conditions and the requirement for solvent recovery.
2Reliability
If large volumes of DMSO are used, then the reaction can proceed, but the amount of water and work-up solvents required increases
Solution Approach 1:
The patent applies local quality by using different solvents in different phases: DMSO in the reaction phase for effectiveness, and organic solvents (ethyl acetate, toluene) in the extraction phase for product isolation. This localized solvent selection optimizes each stage while managing overall solvent quantities.
Solution Approach 2:
The workup process is segmented into multiple extraction steps using different organic solvents. This segmentation allows progressive removal of DMSO and isolation of the product, reducing the total volume of work-up solvents needed compared to a single-step extraction with large volumes.
3Ease of manufacture
If DMSO is used in the etherification step, then the reaction can proceed, but partial decomposition of DMSO occurs reducing yield
Solution Approach 1:
The patent changes the reaction parameters by carefully controlling temperature and adding DMSO in portions rather than as a single large volume. This parameter optimization reduces DMSO decomposition while maintaining reaction proceedability, thereby improving yield.
Solution Approach 2:
The patent employs periodic action by adding DMSO in multiple portions during the etherification reaction rather than all at once. This staged addition allows the reaction to proceed effectively while minimizing decomposition losses, improving overall productivity.
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 significantly reduces solvent usage, simplifies the synthesis process, enhances yield and purity of 9,9-bis(hydroxymethyl)fluorene, and maintains high purity of 9,9-bis(methoxymethyl)fluorene, addressing environmental and cost issues while ensuring efficient production.
Implementation Method 1
An alcoholic solution of sodium alkoxide, such as sodium methoxide in methanol or sodium ethoxide in ethanol is used as a base
Implementation Method 2
adding dimethyl sulfate to obtain 9,9-bis(methoxymethyl)fluorene
Data Source
AI summary
The present invention relates to a novel process for the synthesis of 9,9-bis(hydroxymethyl)fluorene. The syntheses from fluorene to 9,9-bis(hydroxy- methyl)fluorene via a hydroxymethylation and further to 9,9-bis(methoxymethyl)- fluorene via a etherification are known. 9,9-bis(methoxymethyl)fluorene is a compound that is used as an electron donor for Ziegler-Natta catalysts. The present invention is related to an improvement in the synthesis of 9,9-bis(hydroxymethyl)fluorene leading to a decrease in the amount of solvent used and an easier work up while achieving high yield and purity.