N-Aryl-2-nitrosoanilines as Intermediates in the Two-Step Synthesis of Substituted 1,2-Diarylbenzimidazoles from Simple Nitroarenes

Abstract

N-Aryl-2-nitrosoanilines, easily available from reaction of nitroarenes with anilide anions, undergo base-promoted condensation reaction with substituted benzyl aryl sulfones, furnishing 1,2-diaryl-1H-benzimidazoles.

Simple Synthesis of Quinoxalin‐2(1H)‐one N‐Oxides from N‐Aryl‐2‐nitrosoanilines and Alkylated Cyanoacetic Esters

“…The vicinal position of nucleophilic amino—and strongly electrophilic nitroso—groups makes these compounds very interesting starting materials for domino reactions with properly equipped dipolar partners, leading to a variety of heterocyclic systems. It was already shown that reactions of title compounds with comparatively acidic sulfones (Scheme , route 1) or acetates and phosphonoacetates (Scheme , route 2) are efficient ways of synthesis of benzimidazoles and quinoxalin‐2(1 H )‐ones . Here, we would like to report a new reaction of N ‐aryl‐2‐nitrosoanilines with alkylated derivatives of cyanoacetic esters furnishing quinoxalin‐2(1 H )‐one‐4 N ‐oxides in moderate to excellent yields.…”

SN H Arylamination of 3-Nitropyridine: A Competitive Formation of 2-Arylamino-5-nitropyridines and 2-Arylamino-5-nitrosopyridines

“…IR (thin film): 3232, 3023, 2930, 1600, 1571, 1532, 1506 cm -1 . 6, 159.1, 157.2, 135.1, 122.8 (d, 3 J C,F = 7.9 Hz), 119.5 (d, 4 N-(5-Nitropyridin-2-yl)-4-(trifluoromethyl) (d, J = 8.5 Hz, 2 H, H-3′,5′ C 6 H 4 ), 7.71 (d, J = 8.5 Hz, 2 H, H-2′,6′ C 6 H 4 ), 7.01 (d,J = 9.3 Hz,1 H,. Hz, 1 H, H-6 Py), 8.31 (dd, J = 9.3, 2.8 Hz, 1 H, H-4 Py), 7.71 (d, J = 8.9 Hz, 2 H, H-3′,5′ C 6 H 4 ), 7.53 (d, J = 8.9 Hz, 2 H, H-2′,6′ C 6 H 4 ), 6.92 (d,J = 9.3 Hz,1 H,.…”

“…1 H NMR (400 MHz, DMSO-d 6 ): δ = 9.78 (br s, 1 H, NH), 8.94 (d, J = 2.8 Hz, 1 H, H-6 Py), 8.31 (dd, J = 9.3, 2.8 Hz, 1 H, H-4 Py), 7.70 (dd, J = 7.8, 1.5 Hz, 1 H, H-3′ C 6 H 4 Cl), 7.55 (dd, J = 8.0, 1.3 Hz, 1 H, H-6′ C 6 H 4 Cl), 7.39 (ddd, J = 6.7, 8.0, 1.5 Hz, 1 H, H-5′ C 6 H 4 Cl), 7.27 (ddd, J = 7.8, 6.7, 1.3 Hz, 1 H, H-4′ C 6 H 4 Cl), 6.88 (d,J = 9.3 Hz,1 H,. 8, 145.9, 136.4, 135.6, 133.0, 129.9, 128.3, 127.7, 127.3, 126.9, 109. (d, J = 8.0 Hz, 1 H, H-3′ C 6 H 4 ), 7.58 (dd, J = 8.1, 1.2 Hz, 1 H, H-6′ C 6 H 4 ), 7.43 (ddd, J = 8.0, 7.6, 1.2 Hz, 1 H, H-4′ C 6 H 4 ), 7.32 (ddd, J = 8.1, 7.6, 1.4 Hz, 1 H, H-5′ C 6 H 4 ), 7.15 (dd, J = 9.2, 2.0 Hz, 1 H, H-4 Py), 6.79 (d,J = 9.2 Hz,1 H,. 0, 160.0, 158.3, 135.1, 129.6, 128.7, 127.6, 127.5, 127.2, 120.1, 109.4…”

“…IR (thin film): 3347, 3237, 3093, 1594, 1577, 1555, 1394, 1315 cm -1 . 1 H NMR (400 MHz, DMSO-d 6 ): δ = 10.71 (br s, 1 H, NH), 9.13 (d, J = 2.0 Hz, 1 H, H-6 Py), 8.43 (dd, J = 9.1, 2.0 Hz, 1 H, H-4 Py), 8.24 (d, J = 8.9 Hz, 2 H, H-3′,5′ C 6 H 4 ), 8.01 (d, J = 8.9 Hz, 2 H, H-2′,6′ C 6 H 4 ), 7.08 (d,J = 9.1 Hz,1 H,. 158.0, 146.1, 145.3, 141.3, 137.6, 133.1, 125.1, 118.6, 112.…”

Synthesis of 1-arylbenzimidazoles and dibenzo[b,e][1,4]diazepines from 2 (arylamino)aryliminophosphoranes

“…The latter, bearing two differently polarized groups, proved to be valuable starting materials in the synthesis of various nitrogen heterocycles. [3][4][5][6][7][8] An attractive transformation of 2-nitrosodiarylamines appeared to be their smooth reaction with triphenylphosphine, first published in 2014, 9 leading to 2-(arylamino)aryliminophosphoranes via a Cadogan-type reaction. These turned out to be versatile and stable equivalents for 1-aryl-1,2-arylenediamines; they reacted with isocyanates, 9 nitrous acid, 10 CS 2 11 and CO 2 12 furnishing 2-aminobenzimidazoles, benzotriazoles, 2-thiobenzimidazoles and 2-benzimidazolones respectively (Scheme 1).…”