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High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
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Facile conversion of cis into trans oxane as liquid crystals
Zhaoheng Dong1, Ping Fan2, Qun Chen3
1Shandong Shenghua New Material Technology Co., Ltd., Laiyang city, 265110, P.R. China.
Scientific Reports
|April 26, 2020
Summary
This study presents an efficient method for converting toxic cis-oxanes into valuable trans-oxanes using p-toluenesulfonic acid. The new process significantly improves yield and reduces environmental impact compared to traditional synthesis.
Area of Science:
- Organic Chemistry
- Materials Science
- Green Chemistry
Background:
- Trans-oxanes are crucial liquid crystals.
- Conventional synthesis methods produce environmentally harmful cis-oxanes.
- There is a need for sustainable oxane synthesis and waste reduction.
Purpose of the Study:
- To develop an efficient method for cis-oxanes to trans-oxanes conversion.
- To investigate the catalytic activity of p-toluenesulfonic acid for isomerization.
- To optimize reaction conditions for higher yields and reduced environmental impact.
Main Methods:
- Studied the cis to trans isomerization of cis-oxanes using p-toluenesulfonic acid as a catalyst.
- Investigated the effects of various catalysts, reaction times, and temperatures.
- Analyzed the proposed mechanism of the isomerization process.
Main Results:
- Achieved over 70% yield in cis to trans conversion, surpassing traditional methods (42-69%).
- The overall yield of the new method reached 90%.
- Identified optimal conditions for catalyst, reaction time, and temperature.
Conclusions:
- The developed method offers a highly efficient and environmentally friendly route for trans-oxanes production.
- P-toluenesulfonic acid is an effective catalyst for cis-oxanes isomerization.
- This approach significantly improves sustainability in liquid crystal synthesis.
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