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Optimization of solid-supported Glaser-Hay reactions in the microwave
Jessica S Lampkowski1, Johnathan C Maza2, Sanjana Verma3
1Department of Chemistry, College of William & Mary, P.O. Box 8795, Williamsburg, VA 23187, USA. jslampkowski@email.wm.edu.
Molecules (Basel, Switzerland)
|March 27, 2015
Summary
Microwave irradiation significantly accelerates solid-supported Glaser-Hay coupling reactions for diyne synthesis. This method achieves high yields in minutes, outperforming traditional thermal conditions.
Area of Science:
- Organic Chemistry
- Green Chemistry
Background:
- Organometallic reactions offer synthetic advantages.
- Microwave reactors can enhance reaction efficiency and speed.
- Solid-supported reagents simplify purification and catalyst recovery.
Purpose of the Study:
- To adapt a solid-supported Glaser-Hay reaction for microwave conditions.
- To evaluate the efficiency and scope of microwave-assisted diyne synthesis.
- To compare microwave conditions with conventional thermal methods.
Main Methods:
- Application of a pre-existing solid-supported Glaser-Hay reaction protocol.
- Utilizing microwave irradiation for rapid reaction heating.
- Synthesis of various diyne compounds.
Main Results:
- Successful synthesis of an array of diynes under microwave conditions.
- Reaction times reduced from 16 hours (thermal) to 20 minutes (microwave).
- Improved yields and chemoselectivity observed, especially with non-microwave transparent alkynes, preventing catalyst quenching.
Conclusions:
- Microwave-assisted solid-supported Glaser-Hay coupling is a rapid and efficient method for diyne synthesis.
- The technique offers significant time savings and potentially higher yields compared to thermal methods.
- This approach is suitable for chemoselective synthesis and may overcome limitations with certain alkyne substrates.
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