Ammonium formate → Dihydrogenistein
Reaktionsgleichung
[CH:1]1[C:6]([C:7]2[C:16](=[O:17])[C:15]3[C:14]([OH:18])=[CH:13][C:12]([OH:19])=[CH:11][C:10]=3[O:9][CH:8]=2)=[CH:5][CH:4]=[C:3]([OH:20])[CH:2]=1.C([O-])=O.[NH4+]>>[OH:18][C:14]1[CH:13]=[C:12]([OH:19])[CH:11]=[C:10]2[C:15]=1[C:16](=[O:17])[CH:7]([C:6]1[CH:5]=[CH:4][C:3]([OH:20])=[CH:2][CH:1]=1)[CH2:8][O:9]2Komponenten
3
Versuchsvorschrift
Compound 22 was prepared following the general procedure described by Wähälä K. and Hase T. A., Heterocycles 28:183-86 (1989), herein incorporated by reference in its entirety. To a 50 mL round bottom flask was added genistein (270 mg, 1 mmol) and ammonium formate (1.08 g, 4 mmol). The flask was purged with N2, followed by addition of methanol (20 mL) and 10% Pd/C (255 mg). Upon consumption of the starting material (measured by reverse phase HPLC), the reaction mixture was passed through a pad of silica gel with EtOAc/Hex as the eluent. The solvent was concentrated in vacuo to afford crude 22. Purified by recrystallization from CHCl3/MeOH to afford 22 (144 mg, 53%) as brown crystals. Analytical data for isoflavanone 22: 1H NMR (500 MHz, DMSO) δ 12.19 (s, 1H), 10.84 (br s, 1H), 9.42 (br s, 1H), 7.08 (d, J=8.5 Hz, 2H), 6.73 (d, J=8.5 Hz, 2H), 5.91-5.90 (s, 2H), 4.53 (d, J=6.5 Hz, 2H), 4.00 (t, J=6.5 Hz, 1H); 13C NMR (125 MHz, DMSO) δ 197.6, 167.4, 164.6, 163.6, 157.4, 130.4, 126.3, 116.0, 102.5, 96.9, 95.5, 49.9; LCMS: Mass calculated for C15H12O5, [M+H]+, 273. Found 273.