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Updated: Jul 14, 2026
05:34
Efficient Synthesis of Polyfunctionalized Benzenes in Water via Persulfate-promoted Benzannulation of α,β-Unsaturated Compounds and Alkynes
Published on: December 16, 2019
Solid-supported acids as mild and versatile reagents for the deprotection of aromatic ethers
Poonsakdi Ploypradith1, Pannarin Cheryklin, Nattisa Niyomtham
1Laboratory of Medicinal Chemistry, Chulabhorn Research Institute, Vipavadee-Rangsit Highway, Bangkok, Thailand 10210. poonsakdi@cri.or.th
Organic Letters
|June 15, 2007
Summary
Immobilized p-Toluene sulfonic acid (p-TsOH) on polystyrene or silica effectively cleaves various aromatic ether protecting groups. This method allows for selective deprotection, even when multiple groups are present on a substrate.
Area of Science:
- Organic Chemistry
- Catalysis
- Protecting Group Chemistry
Background:
- Aromatic ether protecting groups are crucial in organic synthesis.
- Efficient and selective deprotection methods are essential for complex molecule synthesis.
- Developing robust solid-supported catalysts can improve reaction efficiency and simplify purification.
Purpose of the Study:
- To investigate the efficacy of immobilized p-Toluene sulfonic acid (p-TsOH) for cleaving aromatic ether protecting groups.
- To evaluate the performance of p-TsOH immobilized on both polystyrene (PS) and silica (Si) supports.
- To determine the selectivity of the deprotection method in the presence of multiple protecting groups.
Main Methods:
- Synthesis of p-Toluene sulfonic acid immobilized on polystyrene (PS-p-TsOH) and silica (Si-p-TsOH).
- Application of the immobilized catalysts for the cleavage of various aromatic ethers.
- Analysis of reaction products to determine yield and selectivity.
Main Results:
- Immobilized p-TsOH on both PS and Si demonstrated effectiveness in cleaving isopropyl, tert-butyl, allyl, and benzyl ether protecting groups.
- Moderate to excellent yields (54-95%) were achieved for the deprotection reactions.
- Selective deprotection was observed even when multiple aromatic ether protecting groups were present on the same or different aromatic rings within a substrate.
Conclusions:
- Solid-supported p-TsOH is a versatile and effective reagent for the deprotection of aromatic ethers.
- The immobilized catalysts offer a practical approach for selective deprotection in complex synthetic strategies.
- This method provides a valuable tool for organic chemists requiring efficient cleavage of benzyl and related protecting groups.
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