[8-(Benzyloxy)-5-chloroquinolin-7-yl]acetaldehyde → 2-(8-Benzyloxy-5-chloro-quinolin-7-yl)-1-(3-pyrrolidin-1-ylmethyl-phenyl)-ethanol

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a stirring solution of [8-(benzyloxy)-5-chloroquinolin-7-yl]acetaldehyde (10.54 mmol) in tetrahydrofuran (75 mL) at −78° C. was slowly added a 0.25M solution of [3-(1-pyrrolidinylmethyl)phenyl]magnesium bromide in tetrahydrofuran (12.50 mmol, 1.2 eq.) and stirring at −78° C. was continued for 20 min. The reaction mixture was then quenched with saturated aqueous ammonium chloride solution (10 mL) and allowed to warm to room temperature. The mixture was then diluted with saturated aqueous ammonium chloride solution (65 mL) and extracted with ethyl acetate (2×75 mL). The combined organic layers were dried (MgSO4), filtered and concentrated to give 2-(8-benzyloxy-5-chloro-quinolin-7-yl)-1-(3-pyrrolidin-1-ylmethyl-phenyl)-ethanol as a yellow oil that was purified by column chromatography using 70/29/1 dichloromethane/acetone/diisopropylethylamine. The 2-(8-benzyloxy-5-chloro-quinolin-7-yl)-1-(3-pyrrolidin-1-ylmethyl-phenyl)-ethanol was subjected to the general conditions described above for conversion of alcohols to azides to give 7-[2-Azido-2-(3-pyrrolidin-1-ylmethyl-phenyl)-ethyl]-8-benzyloxy-5-chloro-quinoline. 7-[2-Azido-2-(3-pyrrolidin-1-ylmethyl-phenyl)-ethyl]-8-benzyloxy-5-chloro-quinoline (5.34 mmol) was subjected to the general conditions described above for Staudinger reduction of azides to give 2-(8-Benzyloxy-5-chloro-quinolin-7-yl)-1-(3-pyrrolidin-1-ylmethyl-phenyl)-ethylamine an amber oil and was used directly in the ensuing step. 2-(8-Benzyloxy-5-chloro-quinolin-7-yl)-1-(3-pyrrolidin-1-ylmethyl-phenyl)-ethylamine (0.675 mmol) was subjected to the general conditions described above for N-acylation with 4-biphenylcarbonyl chloride to give an off-white solid which was purified by twice recrystallizing from dichloromethane/hexanes to give the title compound as a white solid (0.311 mmol, 18% for 4 steps). MS (ESI) m/z 652.5; HRMS: calcd for C42H38ClN3O2+H+, 652.27253; found (ESI, [M+H]+ Obs'd), 652.2730.

Herkunft & Nachweise