7-FLUOROINDOLINE synthesis

Yield:769966-04-3 99%

Reaction Conditions:

Stage #1: 7-fluoro-1H-indolewith sodium cyanoborohydride;acetic acid at 20; for 2 h;
Stage #2: with sodium hydroxide in water;

Steps:

30.A

Reference Example 30 7-fluoro-5-(methylsulfonyl)-2,3-dihydro-1H-indole hydrochloride (A) 7-fluoro-2,3-dihydro-1H-indole; To a solution of 7-fluoroindole (20.0 g, 148 mmol) in acetic acid (60 mL) was added sodium cyanoborohydride (18.7 g, 298 mmol) by small portions, and the mixture was stirred at room temperature for 2 hr. The reaction mixture was added to 2M aqueous sodium hydroxide solution (1500 mL), and the mixture was extracted with dichloromethane. The extract was washed with saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (ethyl acetate:hexane=40:60 - 100:0) to give the title compound (20.0 g, yield 99%). ¹H-NMR (300 MHz, CDCl₃) δ: 3.08 (t, J = 8.4 Hz, 2H), 3.62 (t, J = 8.4 Hz, 2H), 6.62-6.66 (m, 1H), 6.78-6.83 (m, 1H), 6.90 (dd, J = 7.6, 0.4 Hz, 1H).

References:

EP2399914,2011,A1 Location in patent:Page/Page column 97