Oxidative Coupling of N-Methoxyamides and Related Compounds toward Aromatic Hydrocarbons by Designer μ-Oxo Hypervalent Iodine Catalyst

Toshifumi Dohi; Hirotaka Sasa; Mio Dochi; Chihiro Yasui; Yasuyuki Kita

doi:10.1055/s-0037-1611661

Synthesis, Table of Contents

CC BY-ND-NC 4.0 · Synthesis 2019; 51(05): 1185-1195
DOI: 10.1055/s-0037-1611661

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Oxidative Coupling of N-Methoxyamides and Related Compounds toward Aromatic Hydrocarbons by Designer μ-Oxo Hypervalent Iodine Catalyst

Toshifumi Dohi *

^aCollege of Pharmaceutical Sciences, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga, 525-8577, Japan Email: td1203@ph.ritsumei.ac.jp

,

Hirotaka Sasa

^aCollege of Pharmaceutical Sciences, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga, 525-8577, Japan Email: td1203@ph.ritsumei.ac.jp

,

Mio Dochi

^aCollege of Pharmaceutical Sciences, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga, 525-8577, Japan Email: td1203@ph.ritsumei.ac.jp

,

Chihiro Yasui

^aCollege of Pharmaceutical Sciences, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga, 525-8577, Japan Email: td1203@ph.ritsumei.ac.jp

,

Yasuyuki Kita *

^bResearch Organization of Science and Technology, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga 525-8577, Japan Email: kita@ph.ritsumei.ac.jp

› Author Affiliations

Abstract

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Published as part of the 50 Years SYNTHESIS – Golden Anniversary Issue

Abstract

Oxidative coupling strategies that can directly convert the C–H group for chemical transformations are, in theory, ideal synthetic methods to reduce the number of synthetic steps and byproduct generation. Hypervalent iodine reagents have now become one of the most promising tools in developing oxidative couplings due to their unique reactivities that are replacing metal oxidants. As part of our continuous development of oxidative coupling reactions, we describe in this report highly efficient μ-oxo hypervalent iodine catalysts for the direct oxidative coupling of N-methoxyamides and related compounds with aromatic hydrocarbons. The excellent TONs, up to over 100 times, with a best catalyst loading of 0.5 mol% were determined for the oxidative C–H/N–H coupling method, which can provide the most straightforward route to obtaining these unique arylamide compounds.

Key words

hypervalent compound - iodine - oxidative coupling - amidation - electrophilic substitution

Full Text

References

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