To a solution of 5-[3-bromo-3-(tert-butyl-dimethyl-silanyloxy)-butyl]-pyrrolidin-2-one (750 mg, 1.76 mmol) in DME (15 mL) was added phenylboronic acid (236 mg, 1.93 mmol). Palladium acetate (26.8 mg, 0.120 mmol) and tri-o-tolylphosphine (39.5 mg, 0.130 mmol) were added, followed by a solution of Na2CO3 (373 mg, 3.52 mmol) in water (1.8 mL). The reaction mixture was heated under reflux for 24 h. The reaction mixture was cooled and the volatiles were removed in vacuo. The residue was diluted with brine and EtOAc. The aqueous solution was washed with EtOAc (3×) and the combined organic extracts were dried (MgSO4), filtered and concentrated. Purification by medium pressure chromatography eluting with a solvent gradient (1:1 hexanes:EtOAc to EtOAc to 1% MeOH in CH2Cl2 to 3% MeOH in CH2Cl2 to 5% MeOH in CH2Cl2) provided 5-[4-biphenyl-3-yl-3-(tert-butyl-dimethyl-silanyloxy)-butyl]-pyrrolidin-2-one (717.3 mg). 1H NMR (CDCl3) δ7.57 (m, 2H), 7.43 (m, 2H), 7.33 (m, 3H), 7.11 (m, 2H), 5.78 (m, 1H), 3.91 (m, 1H), 3.59 (m, 1H), 2.76 (m, 2H), 2.27 (m, 3H), 1.73-1.38 (m, 5H), 0.83 (s, 9H), −0.03 (d, 3H), −0.16 (d, 3H); MS 424.3 (M+1).
