Remote C-H Amination and Alkylation of Camphor at C8 through Hydrogen-Atom Abstraction
Goh Sennari1,2, Hiroki Yamagishi1, Richmond Sarpong1
1Department of Chemistry, University of California, Berkeley, California 94720, United States.
Abstract:
Camphor continues to serve as a versatile chiral building block for chemical synthesis. We have developed a novel method to functionalize the camphor skeleton at C8 using an intramolecular hydrogen atom abstraction. The key advance involves the use of a camphor-derived aminonitrile, which is converted to the corresponding nitrogen-centered radical under photoredox conditions to effect the 1,5-hydrogen atom transfer at C8. The resulting carbon-centered radical at C8 was utilized in a C-H amination to access topologically complex proline derivatives. Furthermore, the total synthesis of several sesquiterpenoids was accomplished by engaging the radical generated at C8 in alkylation reactions.
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