The selective synthesis of N-arylbenzene-1,2-diamines or 1-arylbenzimidazoles by irradiating 4-methoxy-4′-substituted-azobenzenes in different solvents

Abstract

A solvent-controllable photoreaction involving 4-methoxyazobenzenes has been developed to synthesize 1-aryl-1H-benzimidazoles or N-arylbenzene-1,2-diamines in moderate to good yields.

Synthesis of Phenols from Aryl Ammonium Salts under Mild Conditions

“…13 C­{ 1 H} NMR (101 MHz, DMSO- d ) δ 160.9, 152.1, 145.2, 130.4, 129.3, 124.8, 122.1, 115.9. All spectral data match those previously reported …”

“…All spectral data match those previously reported. 22 Synthesis of 4-Hydroxybenzonitrile (4). Following the general procedure, the crude product was purified using silica gel column chromatography (hexane−AcOEt = 8:1) to produce the desired product 4; 4 was isolated as a white solid (140 mg, 98% yield); 1 H NMR (400 MHz, DMSO-d) δ 10.65 (s, 1H), 7.66 (d, J = 8.8 Hz, 2H), 6.93 (d, J = 8.8 Hz, 2H).…”

“…All spectral data match those previously reported. 35 Synthesis of 2-Hydroxy-6-methylpyridine (22). Following the general procedure, the crude product was purified using silica gel 36 Synthesis of 2-Hydroxy-3-bromopyridine (23).…”

Microwave-assisted rapid and sustainable synthesis of unsymmetrical azo dyes by coupling of nitroarenes with aniline derivatives

“…88°C]; 1 H NMR (400 MHz, CDCl 3 ): δ 7.93 (d, J = 8.8 Hz, 2H), 7.66 (dd, J = 8.4, 2.4 Hz, 1H), 7.54 (dd, J = 8.4, 2.4 Hz, 1H), 7.40–7.28 (m, 2H), 6.94 (d, J = 8.8 Hz, 2H); 13 C NMR (100 MHz, CDCl 3 ): δ 158.9, 148.8, 147.4, 134.7, 131.1, 130.6, 127.3, 125.6, 117.6, 115.9; Elemental analysis calcd (%) for C 12 H 9 ClN 2 O: C, 61.95; H, 3.90; N, 12.04; found: C 61.82, H 3.82, N 11.93. ( E )-4-((4-Bromophenyl)diazenyl)phenol, 3k: ( Chen et al., 2021 ) pale orange solid, 89% m.p. 153–155°C [Lit.…”

“…( E )-4-((4-Bromophenyl)diazenyl)phenol, 3k: ( Chen et al., 2021 ) pale orange solid, 89% m.p. 153–155°C [Lit.…”