Bromine → 2-Bromo-7-iodo-9H-fluoren-9-one

Participants

Reaction Steps

A suspension of 2-iodofluoren-9-one (1.046 g, 3.42 mmol; Maybridge) and iodobenzene diacetate (1.21.g, 3.76 mmol; Aldrich) in 1:1 Ac2O-HOAc (10 mL) was treated with bromine (180 μL, 3.48 mmol; Aldrich) followed by 3 drops concentrated sulfuric acid. The mixture solidified, so it was diluted with acetic acid until it could be stirred. After 2 h, the reaction was quenched with aq. Na2S2O3, neutralized with K2CO3, and filtered. The solid filter cake was washed with water, dried, and recrystallized from hot EtOH to afford the title compound (1.05 g, 2.73 mmol; 80% yield): 1H NMR (300 MHz, CDCl3) δ ppm 7.97 (dd, J=2, 1 Hz, 1H), 7.84 (dd, J=8, 2 Hz, 1H), 7.75-7.79 (m, 1H), 7.63 (dd, J=8, 2 Hz, 1H), 7.39 (d, J=7 Hz, 1H), 7.24-7.31 (m, 1H); MS (DCl/NH3): m/z 384 (M+1)+, 386 (M+3)+.

Provenance & Evidence