Oxygen → (R,S)-Equol

Participants

Reaction Steps

A suspension of Palladium-on-charcoal (10%, 2.2 g) in glacial acetic acid (15 ml) was treated with oxygen for three days. The suspension catalyst was added to the solution of 4′,7-dihydroxy isoflavone (0.5 g, mmol) in diglume (60 ml). After 30 min. of catalytic hydrogenation at atmospheric pressure, the solution was filtered and washed with diglume and hot acetic acid. The combined filtrate were evaporoted by using water vacuum pump followed by high vacuum pump. The crude was dissolved in ethylacetate and wished with sodium bicarbonate (5%) and with water till neutral, dried (MgSO4) filtred and evaporeted to give pale white crude (0.385 g) which was recrystallized in aquoes ethanol to give 22a as white crystals (0.361 g), m.p. 156-158° C. (lit. 158° C.). Rfs=IR (KBr) 3380-2720 cm−1. δH (acetone-d6) 2.89 (2H, m, C-4-H2), 3.1 (1H, m, C-3-H) 3.94 (1H, t, J=10.38 Hz, C-2-HA), 4.18 (1H, m, C-2-HE), 6.29 (1H, d, JC-8-H & C-6-H=2.44 Hz, C-8-H), 6.37 (1H, dd, JC-6-H & C-7-H=-8.24 Hz, JC-6-H & C-8-H=2.44 Hz, C-6-H), 6.82 (2H, dd, JC-3′-H & C-2′-H=8.55 Hz. JC-3′ & C-5-H=2.74 H-z,C-3′-H and C-5′-H or C-2′-H and c-6′-H), 6.89 (1H, d, JC-5-H & C-6-H=8.24 Hz, C-5-H), 7.16 (2H, dd, JC-2′-H & C-5′-H=8.24 Hz, JC-2′-H & C-6′-H=2.74 Hz, C-2′-H and C-6′-H or C-3′-H and C-5′-H), 8.15 (1H, br s, C-7-OH or C-4′-OH) and 828 (1H br s, C-4′—OH or C-7-OH). 13CNMR (acetone-d6) MS: m/z (+ve ion FAB in m-NBA, rel. intensity) 242.1 [100, (M)+], [, (M−SO2NH2)+]. MS: m/z (−ve ion FAB in m-NBA, rel. intensity) 394.2 [50, (M−H+NBA)−], 241.2 [100, (M−H)−]. Acc. MS (+ve ion FAB in m-NBA): m/z 242.094 C15H15O3 requires 243.1021. Found: C,; H, 4. C15H14O3 requires C, 74.36; H, 5.82%.

Provenance & Evidence