Structural investigations of C-nitrosobenzenes. Part 1. Solution state 1H NMR studies

Improved Photocontrol of α‐Chymotrypsin Activity: Peptidomimetic Trifluoromethylketone Photoswitch Enzyme Inhibitors

“…This involved coupling of racemic 11 a to an aryl amine, followed by condensation with a nitrosobenzene to form the azobenzene moiety and oxidation to give the trifluoromethylketone. In particular, compounds 6 and 7 were prepared by coupling of 4‐nitrosulfonyl chloride 17 to 11 a to give sulfonamide 18 , catalytic reduction to 19 , condensation with nitrosobenzenes 20 10, 11 and 21 12, 13 to give the azobenzenes 22 and 23 , respectively, and finally oxidation using TEMPO to give ketones 6 and 7 , respectively. Compounds 8 and 9 were similarly prepared, using 3‐nitrosulfonyl chloride 24 as starting material instead of 17 .…”

“…( E )‐[ N ‐(1‐Benzyl‐3,3,3‐trifluoro‐2‐hydroxypropyl)‐4‐(4‐iodophenylazo)benzenesulfonamide] (23) : A suspension of 19 (130 mg, 0.34 mmol) and 4‐iodonitrosobenzene 21 12, 13 (79 mg, 0.34 mmol) in AcOH (1.5 mL) was stirred at 100 °C for 4 h. The reaction mixture was cooled to RT then diluted with water/CH 2 Cl 2 (1:1, 50 mL). Solid Na 2 CO 3 was added until effervescence ceased and the aqueous layer was basic to litmus.…”

“…Solid Na 2 CO 3 was added until effervescence ceased and the aqueous layer was basic to litmus. The aqueous layer was back-extracted with CH 2 Cl 2 and the combined organics were washed with 10 % aqueous HCl, saturated aqueous NaHCO 3 (E)-[N-(1-Benzyl-3,3,3-trifluoro-2-hydroxypropyl)-4-(4-iodophenylazo)benzenesulfonamide] (23): A suspension of 19 (130 mg, 0.34 mmol) and 4-iodonitrosobenzene 21 [12,13] (79 mg, 0.34 mmol) in AcOH (1.5 mL) was stirred at 100 8C for 4 h. The reaction mixture was cooled to RT then diluted with water/CH 2 Cl 2 (1:1, 50 mL). Solid Na 2 CO 3 was added until effervescence ceased and the aqueous layer was basic to litmus.…”

X-ray diffraction and spectroscopic verification of dimerization in hexasubstituted para-nitrosophenols

“…p à nitrosogroup transition in the monomer molecules. However, nitrosobenzenes in the solid form represent a pale-yellow crystalline matter due to the molecule dimerization [2,3].…”

Aromatic C-Nitroso Compounds and Their Dimers: A Model for Probing the Reaction Mechanisms in Crystalline Molecular Solids

“…Such a system is simple because it includes the formation and/or breaking of only one chemical bond between two nitrogen atoms during the dimerization of C-nitroso compounds to the Z-or E-azodioxy dimers, or their subsequent dissociation to the starting monomers (Scheme 1) [32][33][34][35][36][37][38][39]. Although most of the aromatic C-nitroso compounds appear as Z-or E-azodioxides in solid state, certain nitrosobenzene derivatives, such as those with strong electron-donating substituents in the para-position (e.g., p-nitrosoanisoles and p-nitrosoanilines), prefer a monomeric form.…”