Cesium carbonate → Biphenyl

Participants

Reaction Conditions

Reaction Steps

Isoxazolidine 215 (302 mg, 0.505 mmol), pinacol boronate 49 (368 mg, 1.26 mmol), Pd(dppf)Cl2 (82 mg, 0.101 mmol), potassium acetate (65 mg, 0.657 mmol), and cesium carbonate (494 mg, 1.52 mmol) were dissolved in anhydrous DMSO (5 mL) and flushed under positive argon pressure. The reaction mixture was stirred at 60° C. for 2 h, then allowed to cool to ambient temperature. The reaction mixture was diluted with EtOAc (20 mL) and water (10 mL) and the aqueous phase was adjusted to pH 4 with 6M HCl. The reaction mixture was extracted with EtOAc (3×100 mL) and the combined organics were dried (MgSO4), filtered and concentrated to an oil. The crude oil was purified by gradient flash chromatography (10-35% Acetone/hexanes) to afford 170 mg (53%) of biphenyl acid 216.

Provenance & Evidence