N,N'-Dimethylethylenediamine → 6-chloro-7-fluoro-1-(1-propyl-1H-pyrazol-4-yl)-1H-indole

Participants

Reaction Conditions

Reaction Steps

To a stirred solution of compound 2 (1.1 g, 6.48 mmol) in toluene (15 mL) under inert atmosphere were added N,N′-dimethyl ethylene diamine (229 mg, 2.60 mmol), potassium phosphate (3.44 g, 16.27 mmol), 4-bromo-1-propyl-1H-pyrazole (Intermediate B; 1.21 g, 6.50 mmol), CuI (124 mg, 0.65 mmol) at RT, degassed under argon for 15 min; heated to 140° C. and stirred for 20 h in sealed tube. The reaction was monitored by TLC; after completion of the reaction, the reaction mixture was diluted with EtOAc (30 mL), filtered and the filtrate was concentrated under reduced pressure to obtain the crude. This was purified by silica gel column chromatography using 8-10% EtOAc/Hexanes to afford compound 3 (1.3 g, 72%) as brown liquid. 1H NMR (500 MHz, CDCl3): δ 7.64 (s, 1H), 7.60 (s, 1H), 7.31 (d, J=7.5 Hz, 1H), 7.12-7.07 (m, 2H), 6.60 (s, 1H), 4.13 (t, J=7.0 Hz, 2H), 1.99-1.91 (m, 2H), 0.97 (t, J=8.0 Hz, 3H); LC-MS (ESI): 93.5%; m/z 278.2 (M+H+); (column: X Select CSH C-18, 50×3.0 mm, 3.5 μm); RT 4.08 min; 5 mM NH4OAc: ACN; 0.8 mL/min).

Provenance & Evidence