Iodine/DMSO promoted oxidation of benzylic Csp3–H bonds to diketones – A mechanistic investigation

I2-Catalyzed Carbonylation of α-Methylene Ketones to Synthesize 1,2-Diaryl Diketones and Antiviral Quinoxalines in One Pot

“…Thus, the reaction conditions were optimized as 10 mol % I 2 and 3.0 equiv TBHP in DMF at 100 °C for 5 h (Table , entry 3). In comparison to the previously reported literatures, , our current work had two improvements. One difference is that the amount of catalyst I 2 was reduced from 50 mol % to 10 mol % in the preceding literature.…”

“…1,2-Diaryl diketones are a vital class of organic compounds frequently found in structural units of natural products and bioactive molecules. − They are also versatile intermediates used in the synthesis of biologically active heterocyclics, such as imidazoles, − quinoxalines, − indoles, pyrazines, and triazines. − Furthermore, 1,2-diaryl diketones could be transformed into greatly important functional materials with electronic and photochemical properties. − Therefore, various traditional and modern methods for the formation of 1,2-diaryl diketones have been reported, involving the oxidation of α-halo and α-hydroxyl ketones, − alkene and alkyne oxidation, − oxidative cleavage of 1,3-diketones, − benzyl phenyl ketone oxidation, − oxidative decarboxylative coupling of arylpropiolic/cinnamic acids with arylboronic acids or aryl halides, − and oxidative rearrangement of α,β-unsaturated diaryl ketones . Among the above methods, the direct oxidation of benzyl phenyl ketone has emerged as a powerfully straightforward strategy to synthesize 1,2-diaryl diketones.…”

Ruthenium(II)‐Catalyzed Cross‐Coupling of Benzoyl Formic Acids with Toluenes: Synthesis of 2‐Phenylacetophenones

“…3 a (1.0 mmol, 0.196 g) and iodine (0.5 mmol, 0.126 g) were mixed in a round bottomed flask with 1 mL DMSO and heated to 100 °C for 2 h. After cooling, a Na 2 S 2 O 3 /water solution was added to the reaction mixture, extracted with dichloromethane and dried over anhydrous Na 2 SO 4 . Removal of the solvent, under vacuum, afforded the 5 (203 mg, 97 %) which was purified by column chromatography using 5 : 1 hexane:ethyl acetate [14] …”

“…Removal of the solvent, under vacuum, afforded the 5 (203 mg, 97 %) which was purified by column chromatography using 5 : 1 hexane:ethyl acetate. [14] 3 a (1.0 mmol, 0.196 g), iodine (1 mmol, 0.252 g) and sodium methoxide (2 mmol, 0.252 g) were mixed in a round bottomed flask with 140 mL MeOH at room temperature for 12 h. After completion, a Na 2 S 2 O 3 /water solution was added to the reaction mixture, extracted with dichloromethane and dried over anhydrous Na 2 SO 4 . Removal of the solvent, under vacuum, afforded the 6 (196 mg, 93 %) which was purified by column chromatography using 3 : 1 hexane:ethyl acetate.…”

Experimental and DFT Studies on Cp*Co(III)-Catalyzed Selective C8-Olefination and Oxyarylation of Quinoline N-Oxides with Terminal Alkynes

“…Post-functionalizations of the oxyarylated product (4zu) were also performed (Scheme 6). Oxidation of benzylic C(sp 3 )-H bond afforded diketone product 5a 23 , whereas reaction of 4zu with formaldehyde afforded product 5b. 24 Corresponding ketoxime (5c) 25 and alcohol (5d) were also synthesized from 4zu.…”