Sodium borohydride → 4-[4-[4-(2-Fluoroethyl)-1-piperazinyl]-1-piperidinyl]-2-(methyloxy)aniline

Participants

Reaction Steps

A solution of 1-(2-fluoroethyl)-4-{1-[3-(methyloxy)-4-nitrophenyl]-4-piperidinyl}piperazine (15.94 g, 43.50 mmol) in tetrahydrofuran (200 mL) and methanol (300 mL) was cooled to 0° C. Nickel(II) chloridehexahydrate (5.18 g, 21.80 mmol) was added in one portion. The solution was stirred for 30 minutes followed by portion-wise addition of sodium borohydride (3.29 g, 87.00 mmol). Prior to warming the reaction to room temperature additional nickel (II) chloridehexahydrate (5.18 g, 21.80 mmol) and sodium borohydride (3.29 g, 87.00 mmol) were added to the reaction. The solvent was removed in vacuo and the residue was taken up in dichloromethane, filtered through celite, and washed with ethyl acetate. Purification by flash chromatography provided 4-{4-[4-(2-fluoroethyl)-1-piperazinyl]-1-piperidinyl}-2-(methyloxy)aniline (13.46 g, 40.10 mmol, 92%) as a white solid. 1H NMR (400 MHz, DMSO-d6) δ ppm 1.46 (qd, J=11.9, 3.6 Hz, 2 H) 1.76 (d, J=12.1 Hz, 2 H) 2.12-2.20 (m, 1 H) 2.35-2.45 (m, 10 H) 2.53 (dt, JHF=28.6 Hz, J=4.9 Hz, 2 H) 3.37 (d, J=12.1 Hz, 2 H) 3.68 (s, 3 H) 4.14 (br. s., 2 H) 4.47 (dt, JHF=47.9 Hz, J=4.94 Hz, 2 H) 6.24 (dd, J=8.2, 2.4 Hz, 1 H) 6.43 (d, J=2.4 Hz, 1 H) 6.45 (d, J=8.4 Hz, 1 H).

Provenance & Evidence