TY - JOUR
T1 - Catalytic Alkene Carboaminations Enabled by Oxidative Proton-Coupled Electron Transfer
AU - Choi, Gilbert J.
AU - Knowles, Robert R.
N1 - Publisher Copyright:
© 2015 American Chemical Society.
PY - 2015/7/29
Y1 - 2015/7/29
N2 - Here we describe a dual catalyst system comprised of an iridium photocatalyst and weak phosphate base that is capable of both selectively homolyzing the N-H bonds of N-arylamides (bond dissociation free energies ∼ 100 kcal/mol) via concerted proton-coupled electron transfer (PCET) and mediating efficient carboamination reactions of the resulting amidyl radicals. This manner of PCET activation, which finds its basis in numerous biological redox processes, enables the formal homolysis of a stronger amide N-H bond in the presence of weaker allylic C-H bonds, a selectivity that is uncommon in conventional molecular H atom acceptors. Moreover, this transformation affords access to a broad range of structurally complex heterocycles from simple amide starting materials. The design, synthetic scope, and mechanistic evaluation of the PCET process are described.
AB - Here we describe a dual catalyst system comprised of an iridium photocatalyst and weak phosphate base that is capable of both selectively homolyzing the N-H bonds of N-arylamides (bond dissociation free energies ∼ 100 kcal/mol) via concerted proton-coupled electron transfer (PCET) and mediating efficient carboamination reactions of the resulting amidyl radicals. This manner of PCET activation, which finds its basis in numerous biological redox processes, enables the formal homolysis of a stronger amide N-H bond in the presence of weaker allylic C-H bonds, a selectivity that is uncommon in conventional molecular H atom acceptors. Moreover, this transformation affords access to a broad range of structurally complex heterocycles from simple amide starting materials. The design, synthetic scope, and mechanistic evaluation of the PCET process are described.
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U2 - 10.1021/jacs.5b05377
DO - 10.1021/jacs.5b05377
M3 - Article
C2 - 26166022
AN - SCOPUS:84938366327
SN - 0002-7863
VL - 137
SP - 9226
EP - 9229
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
IS - 29
ER -