Tandem C–O and C–N Bonds Formation Through O-Arylation and [3,3]-Rearrangement by Diaryliodonium Salts: Synthesis of N-Aryl Benzo[1,2,3]triazin-4(1H)-one Derivatives

Abstract

Metal-free O-arylation and [3, 3]-rearrangement have been shown as an efficient strategy to construct new C-O and C-N bonds in one-pot reactions. The method was used to prepare N-aryl benzo[1,2,3]triazin-4(1H)-one derivatives in good yields from N-hydroxy benzo[1,2,3]triazin-4(3H)-one and diaryliodonium salts. The reaction was tolerated a variety of sensitive functional groups such as iodine, nitro, ester, and aldehyde groups. A rational mechanism was proposed based on the experimental results, and the reaction was easily up to gram scale.

Unsymmetrical Aryl(2,4,6-trimethoxyphenyl)iodonium Salts: One-Pot Synthesis, Scope, Stability, and Synthetic Studies

“…All other materials were prepared as described in detail below. Crude reaction mixtures were analyzed by 1 H NMR spectroscopy and thin-layer chromatography (TLC) on silica gel (60 Å F-254) TLC plates and visualized by UV irradiation. Crude material was purified by flash column chromatography on silica gel unless otherwise stated.…”

“…Prepared according to the general procedure above on 5 mmol scale and obtained in 93% yield (2.798 g) as a pale yellow powder. 1 Compound 3. Prepared according to the general procedure above on 5 mmol scale and obtained in 93% yield (2.520 g) as a white powder.…”

“…Prepared according to the general procedure above on 5 mmol scale and obtained in 77% yield (2.251 g) as a white powder. 1 H NMR (400 MHz, DMSO-d 6 ) δ 7.83 (d, J = 8.4 Hz, 2H), 7.47 (d, J = 8.1 Hz, 2H), 7.34 (d, J = 8.5 Hz, 2H), 7.10 (d, J = 7.8 Hz, 2H), 6.46 (s, 2H), 3.95 (s, 6H), 3.86 (s, 3H), 2.90 (septet, J = 6.8 Hz, 1H), 2.28 (s, 3H), 1.16 (d, J = 6.9 Hz, 6H). 13 13 C NMR (101 MHz, DMSO-d 6 ) δ 166.4, 159.4, 145.5, 137.6, 135.0, 131.3 (q, J C−F = 32.4 Hz), 128.1 (q, J C−F = 3.5 Hz), 128.0, 125.4, 123.4 (q, J C−F = 272.8 Hz), 120.3 (br.…”

“…The product was obtained in 81% yield (2.478 g) as a light pink powder. 1 H NMR (400 MHz, DMSO-d 6 ) δ 7.95 (d, J = 1.8 Hz, 2H), 7.83 (s, 1H), 7.48 (d, J = 8.0 Hz, 2H), 7.11 (d, J = 7.9 Hz, 2H), 6.50 (s, 2H), 3.97 (s, 6H), 3.89 (s, 3H), 2.29 (s, 3H). 13 Compound 23.…”

“…Prepared according to the general procedure above on 1 mmol scale and obtained in 85% yield (0.4933 g) as a white powder. 1 H NMR (400 MHz, DMSO-d 6 ) δ 8.86 (d, J = 2.2 Hz, 1H), 8.38 (dd, J = 8.5, 2.3 Hz, 1H), 7.62 (d, J = 8.5 Hz, 1H), 7.47 (d, J = 8.0 Hz, 2H), 7.11 (d, J = 7.9 Hz, 2H), 6.47 (s, 2H), 3.96 (s, 6H), 3.88 (s, 3H), 2.29 (s, 3H). 13 Compound 27.…”