(R)-(3′-(Hydroxymethyl)-6-methyl-4-((tetrahydrofuran-3-yl)oxy)biphenyl-2-yl)methyl acetate 35d (127 mg, 0.36 mmol) was dissolved in 10 mL of dichloromethane, followed by addition of methyl (S)-2-(6-hydroxyl-2,3-dihydrobenzofuran-3-yl)acetate (89 mg, 0.43 mmol) and triphenylphosphine (112 mg, 0.43 mmol). The reaction solution was cooled down to 0° C., followed by addition of diisopropyl azodicarboxylate (87 mg, 0.43 mmol). The reaction solution was warmed up to room temperature and stirred for 12 hours. The resulting solution was concentrated under reduced pressure to obtain the crude title compound methyl 2-((S)-6-((2′-(acetoxymethyl)-6′-methyl-4′-(((R)— tetrahydrofuran-3-yl)oxy)biphenyl-3-yl)methoxy)-2,3-dihydrobenzofuran-3-yl)acetate 35e (189 mg) as a yellow oil, which was used directly in the next step without further purification.
