A solution of intermediate 95a (1.42 g, 6.15 mmol) and triphenyl phosphine (3.22 g, 12.29 mmol) in THF (50 mL), under an atmosphere of argon was treated with 2-(tetrahydro-pyran-2-yloxy)-ethanol (1.25 mL, 9.22 mmol), followed by the dropwise addition of diethyl azodicarboxylate (1.94 mL, 12.29 mmol). The reaction mixture was then stirred at RT for 1 h. Water (0.5 mL) was added and the mixture was concentrated in vacuo. The residue was taken up in EtOAc (8 mL) and cyclohexane was added until triphenylphosphine oxide had precipitated out of solution. This was filtered and the filtrate was concentrated in vacuo. The residue was purified by FCC, using 0-100% EtOAc in cyclohexane to afford the title compound as an orange/brown oil (2.98 g, >100%). LCMS (Method 3): Rt 3.20 min, m/z 360 [MH+].
