Radikalpaarmechanismus der aromatischen Umlagerung von O ‐Alkylsulfinyl‐ N ‐phenylhydroxylaminen

Abstract

Wir haben jetzt die aromatische Umlagerung von 0-Alkylsulfinyl-N-benzoyl-Nphenylhydroxylaminen (3) untersucht. Im Gegensatz zu den extrem instabilen Sulfonylderivaten -sollten die 0-Sulfinylverbindungen isolierbar sein: die 0-Acylierung der Hydroxamsaure 1 durch die reaktiveren Sulfinylchloride sollte schneller, die Umlagerung von 3 -entsprechend der geringeren Aciditat der Sulfinsauren -langsamer verlaufen (vgl. z. B. Lit.', "). Dies sollte kinetische Messungen erlauben.

Syntheses of 5‐alkylthio‐1,3‐diaryl‐1,2,4‐triazoles

“…The reaction mixture was stirred for 18 h at 24 °C, filtered to remove Et 3 N•HCl, concentrated and recrystallized from methanol to give 450 mg (95%) of 6, mp: 178-180 °C; 1 H NMR (400 MHz, CDCl 3 ): δ = 7.96-6.7 (m, 9H, aromatic), 3.05 (s, 3H, SO 2 CH 3 ) ppm; IR (KBr): ν = 3319 (NH), 1665 (CO) cm -1 . The spectral data were similar with those reported [15].…”

Fused-Ring Thiadiazines: Preparation and Crystallographic Characterization of 3-Phenyl Derivative of Benzo-, Pyridio[2,3-e]-, Pyrazino[2,3-e]-, and Tetrafluorobenzo-[1,2,4]thiadiazines

“…The crude product was purified by silica gel column chromatography (CH 2Cl2-hexanes in a 1:3 ratio) followed by recrystallization from a hexanes-toluene (9:1) mixture, which gave 1a (0.44 g, 85% yield; other runs 79-85% yield) as a yellow solid: mp 119.5-120.5 °C (lit. 3 119-120 °C); 1 H NMR (300 MHz, CDCl3) δ 6.44 (dd, J1 ) 7.0 Hz, J2 ) 2.0 Hz, 1H), 6.59 (br s, 1H), 6.74 (dd, J1 ) 7.0 Hz, J2 ) 2.0 Hz, 1H), 6.89-6.99 (m, 2H), 7.39-7.47 (m, 3H), 7.63-7.68 (m, 2H); 13 60 (6, 0.136 g, 0.5 mmol), prepared from amine 5b, in toluene (5 mL) at -15 °C. When PCl5 completely dissolved, 30% aqueous ammonia (1 mL) was added in one portion and stirring continued for 15 min.…”

“…Method B. PCl 5 (0.11 g, 0.53 mmol) was added in one portion to a stirred solution of N -(2-propylthiophenyl)benzamide ( 6 , 0.136 g, 0.5 mmol), prepared from amine 5b , in toluene (5 mL) at −15 °C. When PCl 5 completely dissolved, 30% aqueous ammonia (1 mL) was added in one portion and stirring continued for 15 min.…”