Sodium bis(trimethylsilyl)amide → 4-(3-{2-[3-(Tert-butyl-dimethyl-silanyloxy)-4-phenyl-butyl]-5-oxo-pyrrolidin-1-yl}-propyl)-benzoic acid methyl ester

Participants

Reaction Conditions

Reaction Steps

To a solution of 5-[3-(tert-butyl-dimethyl-silanyloxy)-4-phenyl-butyl]-pyrrolidin-2-one (3.20 g, 9.21 mmol) in DMF (30 mL) at 0° C. was added NaHMDS (1M in THF, 11.5 mL, 11.5 mmol). After 1 h, 4-(3-bromo-propyl)-benzoic acid methyl ester (2.84 g, 11.0 mmol) was added and the reaction mixture was stirred at 70° C. for 18 h. The DMF was removed in vacuo and the residue was dissolved in EtOAc. The organic solution was washed with water, dried (MgSO4), filtered and concentrated. The residue was purified by medium pressure chromatography (30% EtOAc in hexanes) to yield 3.39 g of 4-(3-{2-[3-(tert-butyl-dimethyl-silanyloxy)-4-phenyl-butyl]-5-oxo-pyrrolidin-1-yl}-propyl)-benzoic acid methyl ester. 1H NMR (CDCl3) (selected peaks) δ 7.92 (m, 2H), 7.25-7.09 (m, 7H), 3.86 (s, 3H), 3.80 (m, 1H), 3.61 (m, 1H), 3.46 (m, 1H), 2.90 (m, 1H), 2.78-2.57 (m, 4H), 2.38-2.18 (m, 2H), 0.83 (s, 9H); MS 524.1 (M+1).

Provenance & Evidence