Sodium Azide → 2-azido-4-fluoro-2,3-dihydro-1H-inden-1-one

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Reaction Steps

A solution of 4-fluoro-2,3-dihydro-1H-inden-1-one (1.29 g, 9.34 mmol) and HNIB (5.02 g, 12.1 mmol) in CH3CN (190.0 mL) was refluxed for 1.5 h, until the solution was clear yellow. Upon cooling to r.t., NaN3 (1.21 g, 18.7 mmol) was added and the solution was stirred at r.t. for 12 h. Additional NaN3 (0.50 g, 7.7 mmol) was added and the solution stirred further at r.t. for 4 h. The reaction mixture was concentrated in vacuo, and the residue was taken up in CH2Cl2 (100 mL). This solution was washed with H2O (75 mL), dried (Na2SO4), filtered and concentrated in vacuo. The residue was purified via column chromatography (SiO2, 5:1 hexanes/EtOAc) to give 1.61 g (96% yield) of 2-azido-4-fluoro-2,3-dihydro-1H-inden-1-one: 1H NMR (400 MHz, CDCl3): 7.59 (d, 1H), 7.41 (m, 1H), 7.32 (t, 1H), 4.15 (dd, 1H), 3.55 (dd, 1H), 2.89 (dd, 1H).

Provenance & Evidence