Iodine → 3-iodo-4,5-dihydro-1H-benzo[b]azepin-2(3H)-one

Participants

Reaction Conditions

Reaction Steps

A suspension of 34.2 g (212 mmol) of 2,3,4,5-tetrahydro-1H-[1]-benzazapin-2-one and 224 mL (171.2 g, 1.06 mol) of hexamethyldisilazane in 400 mL of methylene chloride was heated at reflux for 15 min and cooled to 30° C. Iodine (161.5 g, 636 mmol) was added in one portion, the solution heated at reflux for 2.5 h, cooled, and poured into a 0° C. solution of 88.6 g of sodium sulfite in 800 mL of water, with vigorous stirring. The aqueous phase was separated, extracted with methylene choride and the combined organics were washed with water and concentrated in vacuo to approximately 200 mL. Toluene (800 mL) was added, the solution was concentrated to a slurry, and the product collected on a filter. Drying under vacuum gave 36.7 g (60%) of a tan powder. 1H NMR (300 MHz, CDCl3) d 8.47 (1H, bs), 7.3-7.1 (3H, m), 7.06 (1H, d, J=8 Hz), 4.68 (1H, t, J=8.7 Hz), 2.97 (1H, m), 2.80-2.60 (3H, m).

Provenance & Evidence