Rh(III)-catalyzed directed C-H olefination using an oxidizing directing group: mild, efficient, and versatile.
Souvik Rakshit1, Christoph Grohmann, Tatiana Besset
1Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Münster, Germany.
Journal of the American Chemical Society
|February 1, 2011
Summary
This study presents an efficient Rh(III)-catalyzed oxidative olefination using N-methoxybenzamides. The N-O bond serves as an internal oxidant, enabling the selective synthesis of tetrahydroisoquinolinone products.
Area of Science:
- Organic Chemistry
- Catalysis
- Synthetic Methodology
Background:
- Directed C-H bond activation is a powerful tool in organic synthesis.
- Oxidative olefination reactions are crucial for constructing complex molecules.
- N-methoxybenzamides offer a unique directing and oxidizing group.
Purpose of the Study:
- To develop an efficient Rh(III)-catalyzed oxidative olefination of N-methoxybenzamides.
- To explore the use of the N-O bond as an internal oxidant.
- To achieve selective synthesis of tetrahydroisoquinolinone products.
Main Methods:
- Rhodium(III)-catalyzed reaction
- Directed C-H bond activation
- Oxidative olefination using N-methoxybenzamides
Main Results:
- An efficient, mild, practical, selective, and high-yielding oxidative olefination was achieved.
- The N-O bond of N-methoxybenzamides effectively acted as an internal oxidant.
- Selective formation of tetrahydroisoquinolinone products was observed by modifying substituents.
Conclusions:
- This work establishes a novel Rh(III)-catalyzed method for oxidative olefination.
- The developed protocol offers a practical route to valuable tetrahydroisoquinolinone scaffolds.
- The directing/oxidizing group's substituent plays a key role in product selectivity.
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