Water → Rotenol

Participants

Reaction Conditions

Reaction Steps

12-Rotenol Synthesis: Rotenone (2 g, 5 mmol) was suspended in methanol (50 mL) and was cooled to 0° C. in an ice bath. Added solid NaBH4 (770 mg, 20 mmol) in one portion and the mixture was stirred for 1 h at 0° C. The reaction mixture was allowed to come to room temperature. Water (100 mL) was added, extracted with dichloromethane (3×50 mL), washed with brine, dried over anhydrous Na2SO4, filtered, and evaporated to obtain a fluffy solid, which was purified by flash column chromatography on silica gel using EtOAc:Hexane (1:3) to afford rotenol as colorless fluffy solid (1.98 g, 98%). m. p.: 80-82° C.; 1H NMR (CDCl3): δ 7.03 (d, 1H, J=7.96 Hz, 11-H); 6.68 (s, 1H, 1-H); 6.45 (s, 1H, 4-H), 6.44 (d, 1H, J=7.96 Hz, 10-H); 5.19 (t, 1H, J=8.89 Hz, 5′H); 5.07 (s, 1H, 7′H); 4.90 (br s, 2H, 7′-H and 12-H); 4.8-4.9 (ddd, 1H, J=5.14, 5.28, 10.68 Hz, 6a-H); 4.60 (dd, 1H, J=10.08, 10.68 Hz, 6′-Hβ); 4.22 (dd, 1H, J=5.14, 10.08 Hz, 6′-Hα); 3.84 (s, 3H, 3-OCH3); 3.83 (s, 3H, 2-OCH3); 3.37 (dd, 1H, J=4.97, 5.28 Hz, 12a-H); 3.28 (dd, 1H, J=8.89, 15.67 Hz, 4′-Hβ); 2.94 (dd, 1H, J=8.89, 15.67 Hz, 4′-Hα); 1.79 (s, 3H, 8′-CH3); 13C NMR (CDCl3): δ 188.73 (C-12); 167.14 (C-9); 157.73 (C-7a); 149.23 (C-3); 147.19 (C-4a); 143.61 (C-2); 142.83 (C-6′); 129.77 (C-11); 113.14 (C-11a); 112.80 (C-8); 112.40 (C-7′); 110.09 (C-1); 104.68 (C-10); 104.63 (C-12b); 100.70 (C-4); 87.66 (C-5′); 72.04 (C-6a); 66.10 (C-6); 56.13 (OCH3); 55.69 (OCH3); 44.41 (C-12a); 31.12 (C-4′); 17.00 (C-8′).

Provenance & Evidence