Iodine → 4-iodoBenzenepentanoic acid

Participants

Reaction Steps

5-Phenylpentanoic acid (50.0 g, 0.28 mol), iodine (37.77 g, 0.149 mol) and (diacetoxyiodo)benzene (48.0 g, 0.149 mol) are suspended in a mixture of glacial acetic acid (500 mL) and acetic anhydride (500 mL). Concentrated sulfuric acid (2 mL) is added and the suspension stirred for 2 h in the dark, during which the red colour fades. The solvent is removed under reduced pressure until approximately 80 ml remained, and the residue poured into ice-water (1 L) containing sodium metabisulfite (8 g). the resulting precipitate is stirred for 30 min, and then filtered. The crude product is recrystallised from ethanol/water, and then from acetic acid/water to afford the product (58.5 g). NMR showed the expected signals.

Provenance & Evidence