5-Fluoroisatin → 5-fluoro-1,3-dihydro-2H-indol-2-one

Participants

Reaction Conditions

Reaction Steps

A solution of 5-Fluoroisatin (1 g) in Hydrazine hydrate (55%, 10 ml) was heated at 110° C. for 30 minutes. Once the suspension has gone into solution, the reaction was heated at 110° C. for 4 hours, then cooled at 0° C. The precipitate was filtered and washed with water. The solid was suspended in water (10 ml), the pH was lowered to pH2 by addition of HCl conc, and the solution stirred at room temperature for 5 hours. The precipitate was collected, the solid washed with water (2×15 ml) and dried in the vacuum oven at 40° C. (0.26 g, 30%). 1H NMR (400 MHz, DMSO-d6) δ 10.2 (s, 1H); 6.8-7.0 (dd, 2H); 6.6 (m, 1H); 3.2 (s, 2H); LCMS: method D, RT=1.736 min, [MH+=152].

Provenance & Evidence