Ethanol → 1,3-Dioxaindane-4-carboxylic acid

Participants

Reaction Steps

6,7-Methylenedioxy-3-(trifluoroacetyl)isothiochroman-4-one from Step 6 (0.64 g, 2.1 mmol) was dissolved in ethanol (100 mL) and 4-sulfonamidophenylhydrazine hydrochloride (0.56 g, 2.5 mmol) was added. The mixture was heated to reflux for 16 hours, and concentrated. The resultant oily solid was dissolved in ethyl acetate and washed with brine and water, dried over MgSO4 and concentrated. Purification was achieved by flash column chromatography eluting with (1:1) ethyl acetate:hexanes. The appropriate fractions were concentrated and recrystallized from ethyl acetate/hexanes. The product was a light brown solid (0.2 g, 21%): mp 272°14 274° C. 1H NMR (DMSO-d6 300 MHz ) 7.98 (d, J=8.4 Hz, 2H), 7.78 (d, J=8.7 Hz, 2H), 7.44 (bs, 2H), 6.79 (d, J=8.4 Hz, 1H), 6.28 (d, J=8.1 Hz, 1H), 6.14 (s, 2H), 4.09 (s, 2H). Anal.s calc'd for C18H12N3S2O4F3 : C, 47.47; H, 2.66; N, 9.23. Found: C, 47.56; H, 2.73; N, 9.16.

Provenance & Evidence