Novel Highly Regioselective VO(acac)₂/TBHP Mediated Oxidation of o‐Alkenyl Phenols to o‐Hydroxybenzyl Ketones.

Abstract

KetonesKetones Q 0350 Novel Highly Regioselective VO(acac) 2 /TBHP Mediated Oxidation of o-Alkenyl Phenols to o-Hydroxybenzyl Ketones. -In addition to the title reaction of phenols (I) yielding ketones (II), a one-pot conversion of these phenols to benzofurans (V) is reported involving the oxidation and subsequent treatment with TFA. In the case of phenols (III), epoxides (IV) are isolated from the oxidation reaction. Probably, steric factors prevent further rearrangement of the epoxides to the desired ketones. -(LATTANZI*, A.; SENATORE, A.; MASSA, A.; SCETTRI, A.; J. Org. Chem. 68 (2003) 9, 3691-3694; Dip. Chim., Univ. Salerno, I-84081 Baronissi, Salerno, Italy; Eng.) -Klein 35-077

Sensitized Photooxidation of Ortho‐Prenyl Phenol: Biomimetic Dihydrobenzofuran Synthesis and Total 1O2 Quenching†

“…2‐((3,3‐Dimethyloxiran‐2‐yl)methyl)phenol 8 is a known compound (23). 1 H NMR (400 MHz, C 6 D 6 ): δ 7.08–7.06 (2H, m), 7.01–6.96 (2H, m), 2.87 (1H, d, J = 8 Hz), 2.84 (1H, d, J = 8.0 Hz), 2.74 (1H, t, J = 8.0 Hz), 1.55 (3H, s), 1.52 (3H, s).…”

Cu-Catalyzed Oxidative C(sp2)–H Cycloetherification of o-Alkenyl Arenols for the Preparation of Fused Furans

“…During their study, it was observed that the addition of acetic acid or BF 3 • Et 2 O resulted in the formation of benzofuran (Scheme 1c). 20 Later, Liu et al reported dehydrogenative oxygenation of C(sp2)−H bonds of ortho-alkenyl phenols with intramolecular phenolic hydroxy groups to access diverse benzofurans (Scheme 1c). 21 Looking at this background, we realized that there is no report on cycloetherification of the C(sp 2 )−H bond of phenols/naphthols having cyclic olefin on the ortho position.…”