Related Experiment Video
Updated: Jan 27, 2026

Synthesis of Information-bearing Peptoids and their Sequence-directed Dynamic Covalent Self-assembly
Published on: February 6, 2020
One-pot synthesis of benzo[b]fluorenones via a cobalt-catalyzed MHP-directed [3+2]
Shuxian Qiu1, Shengxian Zhai, Huifei Wang
1State Key Laboratory of Chemical Oncogenomics and Key Laboratory of Chemical Genomics, Shenzhen Engineering Laboratory of Nano Drug Slow-Release, Shenzhen Graduate School of Peking University, Shenzhen 518055, China. zhaihb@pku.edu.cn.
Abstract:
We have developed a one-pot synthesis of benzo[b]fluorenones via a cobalt-catalyzed [3+2] annulation of oxabicyclic alkenes followed by a ring-opening/dehydration sequence in good to excellent yields. With the use of 2-(1-methylhydrazinyl)pyridine (MHP), first explored by our group as the bidentate directing group in C-H functionalization of benzoic hydrazides, the new reaction sequence proceeded smoothly and tolerated a wide range of functional groups, featuring facile scalability. Notably, oxygen served as the green oxidant in the reaction system. Careful tuning of the reaction parameters assured the direct synthesis of benzo[b]fluorenones through aromatization of the dihydroepoxybenzofluorenone intermediate.
Related Concept Videos
Dehydration Synthesis
Dehydration synthesis (also called a condensation reaction) is the chemical process in which two molecules covalently link together to form a new molecule, along with the release of a water molecule. Many physiologically important compounds form by dehydration synthesis reactions, such as complex carbohydrates, proteins, DNA, and RNA.
Synthesis of carbohydrates
Sugar molecules are covalently linked together by dehydration synthesis. During the reaction, the hydroxyl (-OH) group from...
Acid-Catalyzed Dehydration of Alcohols to Alkenes
Dehydration of Aldols to Enals: Base-Catalyzed Aldol Condensation
ortho–para-Directing Activators: –CH3, –OH, –⁠NH2, –OCH3
Dehydration of Aldols to Enones: Acid-Catalyzed Aldol Condensation
Ethers from Alcohols: Alcohol Dehydration and Williamson Ether Synthesis
Ethers can be prepared from organic compounds by various methods. Some of them are discussed below,
Preparation of Ethers by Alcohol Dehydration
In this method, in the presence of protic acids, alcohol dehydrates to produce alkenes and ethers under different conditions. For example, in the presence of sulphuric acid, dehydration of ethanol at 413 K yields ethoxyethane, whereas it yields ethene at 443 K.

![Microwave-assisted One-pot Synthesis of N-succinimidyl-4-[18F]fluorobenzoate [18F]SFB](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F2755.jpg&w=3840&q=50)