Selective C-O Coupling Reaction of N-Methoxy Arylamides and Arylboronic Acids Catalyzed by Copper Salt

Abstract

Herein, we report a copper-catalyzed C-O cross-coupling of N‑methoxy amides and arylboronic acids for the synthesis of aryl-N-methoxy arylimides. The fully selective O-arylation of the N‑methoxy amides is found to be greatly prompted by the inexpensive and commercially available CuI. The reaction conditions tolerate a variety of functional groups and promote different reactivities depending on the electronic and steric properties of the distorted substrates.

Copper-Catalyzed Chemoselective O-Arylation of Oxindoles: Access to Cyclic Aryl Carboxyimidates

“…1 H, 13 C, and 19 F NMR spectra were recorded in CDCl 3 and d 6 -DMSO, on a JEOL JNM-ECS spectrometer at operating frequencies of 400 MHz 1 H or 101 MHz 13 C as indicated in the individual spectrum. Chemical shifts (δ) are given in parts per million (ppm) relative to residual solvent (CDCl 3 , δ = 7.26 for 1 H NMR and 77.16 for 13 C NMR, d 6 -DMSO: δ = 2.50 for 1 H NMR and δ = 39.52 for 13 C NMR) and coupling constants (J) in hertz. Data for 1 H NMR spectra are reported as follows: chemical shift (multiplicity, coupling constants, number of hydrogens).…”

“…1 H NMR (400 MHz, CDCl 3 ): δ 7.45− 7.21 (m, 18H), 7.16−7.12 (m, 1H). 13 C NMR (101 MHz, CDCl 3 ): δ 180. 4, 153.7, 152.1, 141.2, 140.7, 129.7, 128.7, 128.4, 128.4, 127.7, 125.9, 124.6, 124.6, 121.0, 120.0, 67 NO 362.1545;found 362.1556.…”

Transition Metal‐FreeO‐Arylation ofN‐Alkoxybenzamides Enabled by Aryl(trimethoxyphenyl)iodonium Salts

“…As previously reported, under metal catalytic and electrochemical conditions, specific arylamides can undergo intramolecular O ‐arylations to form useful heterocyclic skeletons [15,16] . In addition, the only known O ‐arylation approach for hydroxamate esters involves the use of a CuI catalyst at high temperatures (Scheme 1b) [17] . However, this Cu‐mediate transformation is incompatible with para ‐OMe/CF 3 and ortho ‐Me/OMe/NO 2 derived boronic acids and hydroxamate esters substituted with para ‐Me/NO 2 groups.…”

“…[15,16] In addition, the only known O-arylation approach for hydroxamate esters involves the use of a CuI catalyst at high temperatures (Scheme 1b). [17] However, this Cu-mediate transformation is incompatible with para-OMe/CF 3 and ortho-Me/OMe/NO 2 derived boronic acids and hydroxamate esters substituted with para-Me/NO 2 groups.…”

K2CO3-promoted synthesis of amides from 1-aryl-2,2,2-trifluoroethanones and amines under mild conditions

“…55 However, to the best of our knowledge, there have been no reports on the preparation of amides using 1-aryl-2,2,2-triuoroethanones under mild conditions. Based on our group's research on amide bonds, [56][57][58][59] we report the activation of the C(O)-C bond of 1-aryl-2,2,2-triuoroethanones, using amine as the N source to construct amides (Scheme 1e). This method does not require the use of transition-metal catalysts and additional oxidants, providing a convenient approach to C-N bond construction.…”