Reaction #1978612

Reaction equation

3-(4-hydroxy-phenyl)-2H-chromen-7-ol

→

3-(4-Hydroxy-phenyl)-chroman-7-ol

Solvents

MeOH

Conditions

Workup

1. 1
   FiltrationAfter the disappearance of starting material (TLC), the catalyst was filtered through a pad of celite
2. 2
   WashThe celite-pad was washed with 10 mL of THF
3. 3
   FiltrationThe solution was filtered once more
4. 4
   Filtrationthrough filter paper
5. 5
   Otherevaporated
6. 6
   Otherto obtain the brownish solid residue which
7. 7
   Otherwas chromatographed over silica gel
8. 8
   Otherto get (0.169 g, 70%)

Procedure

To a solution of 3-(4-hydroxy-phenyl)-2H-chromen-7-ol (P7) (0.241 g, 1 mmol) in MeOH was added 10% Pd—C (0.050 g). This reaction mixture was hydrogenated at room temperature under 2 atm (30 psi) of H2 pressure for ca. 6 hours. After the disappearance of starting material (TLC), the catalyst was filtered through a pad of celite. The celite-pad was washed with 10 mL of THF then 2×10 mL of MeOH. The solution was filtered once more through filter paper and evaporated to obtain the brownish solid residue which was chromatographed over silica gel using CH2Cl2:MeOH (6:1) to get (0.169 g, 70%) reddish white solid P8. 1H NMR (600 MHz, Acetone-d6) δ,7.08 (d, 2H, J=8.4 Hz, Ar—H2′/H6′), 6.82 (d, 1H, J=7.8 Hz, Ar—H5), 6.80 (d, 2H, J=8.4 Hz, Ar—H3′/H5′), 6.35, (dd, 1H, 2J=7.8 Hz, 3J=2.4 Hz), 6.27 (d, 1H, 3J=2.4 Hz), 4.15 (m, 1H, O—CH), 3.88 (t, 1H, J=10.8 Hz, O—CH), 3.0 (m, 1H, 3-CH), 2.9 (m, 2 H, 4-CH2).

Source