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Surface Functionalization of Metal-Organic Frameworks for Improved Moisture Resistance
Published on: September 5, 2018
Pd/Mo-Catalyzed ortho-Dihydroxylation of Aromatic Rings: Dual-Metal-Mediated C(sp2)-H Functionalization
Dingmei Hu1, Renfeng Du1,2, Yongtao Wang1,2
1Zhejiang Key Laboratory of Low-Carbon Synthesis of Value-Added Chemicals, Department of Chemistry, Zhejiang University, 866 Yuhangtang Rd, Hangzhou310058, China.
Journal of the American Chemical Society
|July 16, 2026
Summary
A novel palladium/molybdenum catalyst enables direct ortho-dihydroxylation of benzoic acids. This method efficiently produces valuable meta-diphenolic compounds, crucial fine chemicals, with a simplified synthetic route.
Area of Science:
- Organic Chemistry
- Catalysis
- Synthetic Methodology
Background:
- Benzoic acids are important precursors in organic synthesis.
- Direct ortho-dihydroxylation of benzoic acids is synthetically challenging.
- Meta-diphenolic compounds are valuable fine chemicals often requiring multi-step synthesis.
Purpose of the Study:
- To develop a direct ortho-dihydroxylation protocol for benzoic acids.
- To investigate the role of a palladium/molybdenum bimetallic catalyst.
- To establish a concise synthetic route to meta-diphenolic compounds.
Main Methods:
- Utilized a Pd/Mo bimetallic catalyst system.
- Employed tert-butyl hydroperoxide (TBHP) as the oxidant.
- Conducted mechanistic studies including radical inhibition and spectroscopic analyses.
Main Results:
- Achieved direct ortho-dihydroxylation of benzoic acids.
- Demonstrated that the Mo component enhances the catalytic activity, particularly the second hydroxylation step.
- Showcased tunability for monohydroxylation by controlling TBHP concentration.
- Confirmed practicality through gram-scale reactions and subsequent derivatizations.
- Established a concise route to meta-diphenolic compounds via decarboxylation.
Conclusions:
- The Pd/Mo bimetallic catalyst system provides an efficient method for direct ortho-dihydroxylation.
- The molybdenum component plays a crucial role in promoting the dihydroxylation reaction.
- This methodology offers a streamlined synthesis of valuable meta-diphenolic compounds.
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