[C:1]([O:5][C:6]([N:8]1[CH2:12][CH2:11][C@H:10]([C@H:13]([OH:16])[CH2:14]O)[CH2:9]1)=[O:7])([CH3:4])([CH3:3])[CH3:2].CC1OCCC1.CC(C)([O-])C.[Na+].C1COCC1.N1C=CN=C1.O>>[C:1]([O:5][C:6]([N:8]1[CH2:12][CH2:11][C@H:10]([C@H:13]2[CH2:14][O:16]2)[CH2:9]1)=[O:7])([CH3:2])([CH3:3])[CH3:4](S)-3-((S)-1,2-Dihydroxyethyl)pyrrolidine-1-carboxylic acid t-butyl ester (230 g, 990 mmol, 1.0 eq.) was combined with MeTHF (4.9 kg, 57 mol) and cooled to 0° C. 2.0 M Sodium t-butoxide in THF (994 mL, 2.0 eq.) was added drop wise over 20 minutes. The mixture was stirred at −1° C. for 15 minutes, then cooled to −7° C. p-Tolylsulfonyl)imidazole (243 g, 1.1 mol, 1.1 eq.) was added and the resulting mixture was stirred at 0° C. for 2 hours. The reaction was quenched with cold H2O (5.7 kg, 320 mol). Hexanes (1.8 kg, 21 mol) was added and the mixture was warmed to 23° C. and stirred for about 30 minutes. The layers were allowed to settle, the phases were separated, and the reaction vessel was rinsed with MeTHF (100 mL). The organic layer (˜8 L) was removed and stored at 5° C. overnight, then filtered through Na2SO4 and concentrated at 60 torr to 30 torr with a water bath at 25° C. to yield the title compound (220 g).
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