Degassed toluene (0.5 L), borolan 88 (10 g, 39 mmol), 2-chloro-1-nitrobenzene (6.3 g, 40 mmol), Pd(PPh3)4 (3 g, 2.6 mmol) and 2M Na2CO3 (200 mL) were mixed under a rapid flow of argon, and the resulting mixture was refluxed overnight. Water (200 mL) and EtOAc (500 mL) were added. The aqueous layer was separated and extracted with EtOAc (2×500 mL), and the combined extracts dried over Na2SO4. The solvent was evaporated at reduced pressure and the crude product purified by column chromatography (20% EtOAc in hexanes) to give 9 g (91%) of the biphenyl intermediate 89 as a yellow solid.
