Zur Farbe der N‐(4′‐Nitrophenacyl)‐arylamine

Abstract

Die N-(4'-Nitrophenacyl)-arylamine 5 , hergestellt aus den Arylaminen 3 und 4-Nitrophenacylbromid (2), haben in Abhangigkeit von den Arylsubstituenten eine gelbe, rote oder violette Farbe. Sie wird zuriickgefiihrt auf intramolekulare Wechselwirkung zwixhen dem Nitrobenzoylsystem als Elektronenacceptor und dem Arylaminteil als Elektronendonator. Bei Acetylierung des Aminstickstoffs geht die Farbe verloren. Fur ein Gleichgewicht zwischen den Aminen 5 und den N-(4'-Nitrostyryl)-arylaminen 7 gibt es keine Hinweise.

Low temperature free-radical reactions initiated with tert-butyl p-benzoylperbenzoate. Selective acyl radical additions to substituted olefins

“…Methyl Octa-2,7-dienoate16 (2). 5-Hexen-l-ol (from Aldrich) was oxidized with pyridinium chlorochromate according to the method of Corey and Suggs16 to give 5-hexenal in 61% yield after distillation (50-52 °C (60 torr)): NMR (CDClg) 1.50-2.20 (m, 4 H), 2.47 (t, 3 H), 4.85 (m, 1 ), 5.10 (m, 1 ), 5.40-6.00 (bm, 1 H), 9.72 (t, 1 H). The aldehyde was subsequently reacted with (carbomethoxymethylene)triphenylphosphorane17 in refluxing benzene overnight.…”

Modular Synthesis of Highly Substituted 3-Azapyrroles by Rh(II)-Catalyzed N–H Bond Insertion and Cyclodehydration

“…p-Toluidine (429 mg, 4.0 mmol, 1.0 equiv) and 2-bromo-4′-nitroacetophenone (976 mg, 4.0 mmol, 1.0 equiv) were treated with sodium hydrogen carbonate (336 mg, 4.0 mmol, 1.0 equiv) in ethanol (10 mL) and water (10 mL) according to General Procedure 2 for 2 h, and then the crude product was purified by recrystallization (CHCl 3 /pentane) to give the title compound 16j (971 mg, 90%) as a red solid: mp 127 °C dec (lit. 147−150 °C); 46 1-(4-Cyanophenyl)-2-(4-tolylamino)ethan-1-one (16k). p-Toluidine (429 mg, 4.0 mmol, 1.0 equiv) and 2-bromo-4′-cyanoacetophenone (896 mg, 4.0 mmol, 1.0 equiv) were treated with sodium hydrogen carbonate (336 mg, 4.0 mmol, 1.0 equiv) in ethanol (10 mL) and water (10 mL) according to General Procedure 2 for 2 h to give the title compound 16k (921 mg, 92%) as an orange solid: mp 126 °C dec; ν max (film) 3322, 2924, 2866, 2230, 1678, 1605, 1516, 1404, and 1-(4-Chlorophenyl)-2-(4-tolylamino)ethan-1-one (16l).…”

“…p -Toluidine (429 mg, 4.0 mmol, 1.0 equiv) and 2-bromo-4′-nitroacetophenone (976 mg, 4.0 mmol, 1.0 equiv) were treated with sodium hydrogen carbonate (336 mg, 4.0 mmol, 1.0 equiv) in ethanol (10 mL) and water (10 mL) according to General Procedure 2 for 2 h, and then the crude product was purified by recrystallization (CHCl 3 /pentane) to give the title compound 16j (971 mg, 90%) as a red solid: mp 127 °C dec (lit. 147–150 °C); 46 ν max (film) 3032, 2924, 2866, 1678, 1601, 1524, and 1346 cm –1 ; 1 H NMR (400 MHz, 22.2 °C, CDCl 3 ) δ 8.37 (2 H, d, J = 8.8 Hz, Ar), 8.18 (2 H, d, J = 8.8 Hz, Ar), 7.05 (2 H, d, J = 8.4 Hz, Ar), 6.65 (2 H, d, J = 8.4 Hz, Ar), 4.74 (1 H, br s, NH), 4.66 (2 H, s, CH 2 ) and 2.26 (3 H, s, CH 3 ); 13 C{ 1 H} NMR (101 MHz, 23.0 °C, CDCl 3 ) δ 194.1 (C=O), 150.7 (Ar), 144.4 (Ar), 139.4 (Ar), 130.0 (2 × ArH), 128.9 (2 × ArH), 127.6 (Ar), 124.1 (2 × ArH), 113.2 (2 × ArH), 51.4 (CH 2 ) and 20.4 (CH 3 ); HRMS (ESI-TOF) m / z [M + H] + calcd for C 15 H 15 N 2 O 3 + 271.1077; found 271.1084.…”