4-[(2-Bromo-2,2-difluoroacetyl)-(2-iodophenyl)amino]piperidine-1-carboxylic acid tert-butyl ester → 4-(3,3-Difluoro-2-oxo-2,3-dihydroindol-1-YL)-piperidine-1-carboxylic acid tert-butyl ester

Participants

Reaction Conditions

Reaction Steps

A mixture of 4-[(2-bromo-2,2-difluoroacetyl)-(2-iodophenyl)amino]-piperidine-1-carboxylic acid tert-butyl ester (1.670 g, 2.98 mmol) and copper (bronze, 0.480 g, 7.55 mmol) in DMSO (15 mL) was heated at 70° C. overnight. The reaction mixture was quenched with water at 0° C. and then extracted with ethyl acetate. The combined organic phase was washed with water and brine, dried over anhydrous Na2SO4 and concentrated. Purification of the residue by flash chromatography to afford the title compound in 93% yield (0.976 g). 1H NMR (300 MHz, CDCl3) δ 7.52-7.40 (m, 2H), 7.12 (t, J=7.5 Hz, 1H), 7.00 (t, J=8.1 Hz, 1H), 4.28-4.13 (m, 3H), 2.77 (t, J=12.9 Hz, 2H), 2.32-2.18 (m, 2H), 1.73 (d, J=12.9 Hz, 2H), 1.45 (s, 9H). 13C NMR (75 MHz, CDCl3) δ 165.5, 165.0, 164.6, 154.5, 142.6, 142.5, 142.4, 133.4, 125.0, 123.6, 120.6, 120.3, 120.0, 113.6, 110.9, 110.3, 107.0, 80.0, 77.5, 77.0, 76.6, 51.0, 43.2, 28.3, 27.9. MS (ES+) m/z 375.3 (M+Na).

Provenance & Evidence