Diisopropylethylamine → Methyl 2-[2-(1-{[(3S,4R)-1-Tert-Butyl-4-(2,4-Difluorophenyl)Pyrrolidin-3-yl]Carbonyl}-1,2,3,6-Tetrahydropyridin-4-yl)-5-Chlorophenyl]Propanoate

Participants

Reaction Steps

N,N-diisopropylethylamine (1.00 mL, 5.76 mmol) was added to a stirred suspension of (3S,4R)-1-tert-butyl-4-(2,4-difluorophenyl)pyrrolidine-3-carboxylic acid (1-7) (0.614 g, 1.92 mmol), methyl 2-[5-chloro-2-(1,2,3,6-tetrahydropyridin-4-yl)phenyl]propanoate (2-3) (0.605 g, 1.92 mmol), O-(7-azabenzotriazol-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate (0.876 g, 2.30 mmol) and 1-hydroxy-7-azabenzotriazole (0.314 g, 2.30 mmol) in N,N-dimethylformamide (3.8 mL) at ambient temperature. After approximately 18 h, the reaction mixture was poured into saturated aqueous sodium bicarbonate and extracted three times with ethyl acetate. The combined organic extracts were washed with water, brine, dried (Na2SO4) and concentrated in vacuo. Purification of the crude residue by flash chromatography on silica gel (gradient elution; 0-15% methanol (containing 10% v/v ammonium hydroxide)/methylene chloride as eluent) provided 2-4 as a pale yellow oil; (m/z (ES) 545 (MH+).

Provenance & Evidence