Multicomponent reactions involving arynes, quinolines, and aldehydes
Anup Bhunia1, Digvijay Porwal, Rajesh G Gonnade
1Organic Chemistry Division, and ‡Center for Materials Characterization, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune - 411008, India.
A novel multicomponent reaction synthesizes benzoxazino quinoline derivatives diastereoselectively using arynes, quinolines, and aldehydes. This efficient method proceeds through 1,4-zwitterionic intermediates, showcasing synthetic versatility with various carbonyl compounds and isoquinoline.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
Background:
- Multicomponent reactions (MCRs) are efficient tools for constructing complex molecules.
- Benzoxazino quinoline scaffolds are of interest in medicinal chemistry.
Purpose of the Study:
- To develop a novel diastereoselective synthesis of benzoxazino quinoline derivatives.
- To explore the scope of aldehydes and the utility of isoquinoline in this MCR.
Main Methods:
- A multicomponent reaction involving arynes, quinolines, and aldehydes.
- Investigation of reaction mechanism via 1,4-zwitterionic intermediates.
- Screening of various carbonyl compounds and isoquinoline derivatives.
Main Results:
- Successful diastereoselective synthesis of benzoxazino quinoline derivatives in good yields.
- Demonstrated the synthetic potential of diverse aldehydes.
- Confirmed the utility of isoquinoline as a nucleophilic trigger.
Conclusions:
- A new, efficient, and diastereoselective MCR for benzoxazino quinoline synthesis has been established.
- The reaction offers a versatile platform for generating diverse derivatives.
- The mechanistic insights provide a foundation for further synthetic development.
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