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Metal-free, photoinduced remote C(sp3)-H borylation.
1Department of Chemistry, Indiana University 800 East Kirkwood Avenue Bloomington IN 47405-7102 USA sicook@iu.edu.
Chemical Science
|September 15, 2023
Summary
This study introduces a metal-free method for C(sp3)-H bond borylation using light. The efficient protocol enables late-stage functionalization of complex molecules, including drug candidates.
Area of Science:
- Organic Chemistry
- Photochemistry
- Synthetic Methodology
Background:
- C(sp3)-H bond functionalization is crucial in organic synthesis.
- Developing metal-free and photo-induced methods offers sustainable alternatives.
- Site-selective borylation of unactivated C(sp3)-H bonds remains challenging.
Purpose of the Study:
- To develop a novel protocol for metal-free, photo-induced borylation of C(sp3)-H bonds.
- To achieve site-selective functionalization distal to an O-oxalate hydroxamic ester.
- To enable late-stage borylation of complex organic molecules.
Main Methods:
- Utilizing visible light irradiation.
- Employing bis(catecholato)diboron as the boron source.
- Employing a substrate with an O-oxalate hydroxamic ester directing group.
Main Results:
- Successful metal-free, photo-induced borylation of unactivated C(sp3)-H bonds.
- High yields and site-selectivity achieved for various substrates.
- Demonstrated applicability to natural product derivatives and drug-like compounds.
Conclusions:
- The developed protocol provides an efficient and selective method for C(sp3)-H borylation.
- This approach offers a valuable tool for late-stage functionalization in medicinal chemistry and natural product synthesis.
- The metal-free and photo-induced nature enhances the sustainability of the transformation.
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