Gold-Catalysed Nitroalkyne Cycloisomerization - Synthetic Utility
Pawan S Dhote1,2, Swapnil V Halnor1,2, Chepuri V Ramana1,2
1Organic Chemistry Division, CSIR- National Chemical Laboratory, Dr.Homi Bhabha Road, Pune, 411008, India.
Chemical Record (New York, N.Y.)
|June 2, 2021
Summary
Gold catalysis enables intramolecular redox cyclization of nitroalkynes, creating new research avenues. This study explores gold complexes and synthetic methods for nitroalkyne cycloisomerization, alongside related metal-catalyzed transformations.
Area of Science:
- Organometallic Chemistry
- Catalysis
- Organic Synthesis
Background:
- Gold-catalyzed intramolecular redox cyclization of o-alkynylnitrobenzenes is a key discovery.
- This reaction has spurred interest in both advancing the cyclization with diverse metals and developing new synthetic methodologies.
- A related area involves generating α-oxo gold carbenes via oxygen transfer to alkynes.
Purpose of the Study:
- To review the internal redox cyclization of nitroalkynes (nitroalkyne cycloisomerization).
- To focus on gold complexes and synthetic methods developed for this transformation.
- To compare with similar transformations catalyzed by other metals to highlight reactivity and diversity.
Main Methods:
- Focus on gold-complex catalyzed nitroalkyne cycloisomerization.
- Discussion of synthetic methods developed by the authors' group and others.
- Inclusion of data on transformations catalyzed by alternative metals.
Main Results:
- Detailed examination of gold-catalyzed nitroalkyne cycloisomerization.
- Presentation of various synthetic approaches and developed gold complexes.
- Comparative analysis showcasing complementary reactivity across different metal catalysts.
Conclusions:
- The internal redox cyclization of nitroalkynes is a versatile reaction with significant potential.
- Gold catalysis offers unique advantages for this transformation, complemented by other metal systems.
- Further exploration of metal-catalyzed cycloisomerizations promises expanded synthetic utility.
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