4-Hydroxybenzoic Acid → 4-Hydroxy-3-iodobenzoic acid (2IPCOOH)

Participants

Reaction Steps

A solution of I2 (1.06 g; 4.18 mmol) and KI (3.41 g; 20.54 mmol) in H2O was added at once to a solution of 4-hydroxybenzoic acid (0.58 g; 4.18 mmol) in 25% NH4OH (22 ml). The reaction mixture turn instantly from black to colourless upon stirring at room temperature. This was evaporated under reduced pressure, diluted to 5 ml with H2O and acidified to pH˜5 with 10% citric acid. The solid formed was filtered off, washed with H2O (2×5 ml) and dried to give title compound (0.91 g; 89%), as colourless solid. 1H-NMR (DMSO-d6) 6.9 (d, 1H, J=8.5 Hz); 7.75 (dd, 1H, J=2, 8.5 Hz); 8.17 (d, 1H, J=2 Hz); 11.4 (s, 1H).

Provenance & Evidence