Ligand-Enabled β-C(sp3 )-H Lactamization of Tosyl-Protected Aliphatic Amides Using a Practical Oxidant
Zhe Zhuang1, Shuang Liu1, Jin-Tang Cheng1
1Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
Abstract:
The development of C(sp3 )-H functionalization reactions that use common protecting groups and practical oxidants remains a significant challenge. Herein we report a monoprotected aminoethyl thioether (MPAThio) ligand-enabled β-C(sp3 )-H lactamization of tosyl-protected aliphatic amides using tert-butyl hydrogen peroxide (TBHP) as the sole oxidant. This protocol features exceedingly mild reaction conditions, reliable scalability, and the use of practical oxidants and protecting groups. Further derivatization of the β-lactam products enables the synthesis of a range of biologically important motifs including β-amino acids, γ-amino alcohols, and azetidines.
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