Potassium Hydroxide → HCID 54420220, compound

Participants

Reaction Steps

4-benzylidene-1,2,3,4-tetrahydro-9-oxo-9H-xanthen-7-carboxylic acid, methyl ester (1.2 g) was hydrolized by treatment with 1% KOH in 95% ethanol (19.5 ml) at reflux temperature for 15 minutes. After cooling and acidification with 37% HCl the precipitate was filtered and washed with methanol and then with water to give 1 g of 4-benzylidene-1,2,3,4-tetrahydro-9-oxo-9H-xanthen-7-carboxylic acid, m.p. 284°-286° C., NMR (CF3COOD) δ ppm: 2.12 (m) (2H, C-2 protons), 3.13 (m) (4H, C-1 and C-3 protons), 7.64 (m) (5H, phenyl protons), 8.14 (d) (1H, C-5 proton), 8.43 (bs) (1H, =CH--), 8.88 (dd) (1H, C-6 proton), 9.38 (d) (1H, C-8 proton).

Provenance & Evidence