Ammonium formate → 5-[4-(4'-Methoxybiphenyl-3-yloxy)-benzyl]-thiazolidine-2,4-dione

To a suspension of 58 (1.25 g, 3.0 mmol) in acetic acid (30 mL) was added ammonium formate (1.50 g, 24 mmol) and 10% Pd on carbon (1.30 g). After vigorous refluxing for 16 h, the mixture was filtered through Celite, which was subsequently washed with ethyl acetate (100 mL). The mixture was washed with water (2×75 mL), 1N NaHCO3 (50 mL), brine (75 mL) then dried (MgSO4), filtered and concentrated in vacuo. The crude product was dissolved in dichloromethane, adsorbed onto silica gel and purified by flash chromatography using hexanes:ethyl acetate (3:7) to yield a white solid (0.48 g, 38%) after concentration then trituration and filtration from hexanes-ethyl acetate (4:1). 1H NMR (400 MHz, DMSO-d6): δ 12.04 (br s, 1H), 7.58 (d, J=8.8 Hz, 2H), 7.43 (t, J=7.6 Hz, 1H), 7.39 (dt, J=8.0, 1.6 Hz, 1H), 7.27 (d, J=8.8 Hz, 2H), 7.22 (t, J=2.0 Hz, 1H), 7.01 (d, J=8.8 Hz, 2H), 7.00 (d, J=9.2 Hz, 2H), 4.91 (dd, J=8.8 and 4.4 Hz, 1H), 3.79 (s, 3H), 3.37 (dd, J=14.4 and 4.4 Hz, 1H), 3.13 (dd, J=14.4 and 8.8 Hz, 1H).

1. temperatureAfter vigorous refluxing for 16 h
2. filtrationthe mixture was filtered through Celite, which
3. washwas subsequently washed with ethyl acetate (100 mL)
4. washThe mixture was washed with water (2×75 mL), 1N NaHCO3 (50 mL), brine (75 mL)
5. dry with materialthen dried (MgSO4)
6. filtrationfiltered
7. concentrationconcentrated in vacuo
8. dissolutionThe crude product was dissolved in dichloromethane
9. custompurified by flash chromatography

ORD record

ord-1163dd3795f34a3e9a09fce32166bdde

Source dataset

uspto-grants-2010_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07718682B2