反应详情

温度

0 °C

At 0° C., diethyl azodicarboxylate (7.6 mL, 48.3 mmol) was added dropwise to a solution of the alcohol of Step 8 (17.47 g, 31.97 mmol), triphenylphosphine (12.60 g, 48.04 mmol) and R-(-)-α-methoxyphenylacetic acid (8.07 g, 48.6 mmol) in 320 mL of anhydrous THF. The mixture was stirred at 0° C. for 30 min and the solvents were evaporated. Flash chromatography of the residue on silica using EtOAc:toluene 2.5:97.5, 5:95 and 7.5:92.5 afforded 21.84 g (98%) of the inverted alcohol as the mandelate ester. [α]D -6.02° (c 1.99, THF). This ester was hydrolyzed to the title alcohol as in Example 1, Method B, Step 8.

1. customthe solvents were evaporated