Oxidation of phenols, pyrocatechols, and hydroquinones to ortho-quinones using benzeneseleninic anhydride

Synthesis and Absolute Configuration of Nocardione A and B, Furano-o-naphthoquinone-Type Metabolites of Nocardia sp. with Antifungal, Cytotoxic, and Enzyme Inhibitory Activities

“…However, this resulted in the ring opening of 9 to give back naphthoquinone 10. Fortunately, Barton's benzeneseleninic anhydride [(PhSeO) 2 O] [6] smoothly oxidized 9 to furnish (R)-nocardione B (2) as dextrorotatory orange needles, m.p. 156.0Ϫ157.0°C, [α] D 27 ϭ ϩ72.6 (CHCl 3 ).…”

Structural Study on a Naturally Occurring Terphenyl Quinone

“…Such typical oxidation agents of phenol as Fremy's salt (K 2 [NO(SO 3 ) 2 ]) 7) and molecular oxygen under basic conditions were ineffective, this being attributable to steric hindrance around the phenyl group. In addition, the oxidation of 5 using IBX (2-iodoxybenzoic acid), 8) chromic acid, CAN (ceric ammonium nitrate) and benzeneselenic acid anhydride 9) resulted in the formation of the undesired 4,5-diphenyl-1,2-benzoquinone as a major product. Although the oxidation of 5 using mCBPO (m-chlorobenzoyl peroxide) 10) provided a complex mixture of products, corresponding diacetate 6 was isolated in a 9% yield from the three steps after two-step transformation (LiAlH 4 and then Ac 2 O in pyridine) according to the procedure reported by Tada and coworkers.…”

“…After being stirred at room temperature for 1.5 h, the reaction mixture was filtered and concentrated to give 2 (3.0 mg, 97% for the 2 steps) as an amorphous purple solid. 2-Chloro-4-methoxy-3,6-diphenylphenol (9). MeOH (60 mL) and AcCl (1.3 mL, 18.3 mmol) were mixed at 0 C for 30 min.…”

Naphthoquinones

“…It is obtained in 80 % yield when 2-naphthol is oxidized by air in the liquid phase with copper(I) chloride as catalyst [63]. Slightly lower yields are obtained when periodic acid and dimethyl formamide [64], iodosobenzene [65], or benzene seleninic anhydride is used as oxidant [66]. A 95 % yield can, however, be obtained with tetramethyloxopiperidinium chloride [26864-01-7] at low temperature [67].…”