C(O[CH:4](OCC)[C:5]1[CH:25]=[CH:24][C:8]([CH2:9][N:10]([CH:18]2[CH2:23][CH2:22][O:21][CH2:20][CH2:19]2)[C:11](=[O:17])[O:12][C:13]([CH3:16])([CH3:15])[CH3:14])=[CH:7][CH:6]=1)C.Cl.[NH2:30][OH:31]>C1COCC1.O.C(Cl)Cl.[Cl-].[Na+].O>[OH:31][N:30]=[CH:4][C:5]1[CH:25]=[CH:24][C:8]([CH2:9][N:10]([CH:18]2[CH2:23][CH2:22][O:21][CH2:20][CH2:19]2)[C:11](=[O:17])[O:12][C:13]([CH3:16])([CH3:15])[CH3:14])=[CH:7][CH:6]=1A solution of tert-butyl 4-(diethoxymethyl)benzyl(tetrahydro-2H-pyran-4-yl)carbamate (A-3) (2.80 kg, 7.12 mol) in THF (28.0 L) and water (2.80 L) is stirred at about 20° C. Hydroxylamine hydrochloride (593 g, 8.54 mol) is added while maintaining the reaction temperature between 20-25° C. The reaction mixture is stirred at about 20° C. for 16-20 h then diluted with CH2Cl2 (8.4 L) and 50% brine (11.2 L) and stirred for at least 5 min. The phases are separated then the organic phase is washed with 50% brine (2×2.8 L), dried (Na2SO4) and concentrated. The concentrate is diluted with MeOH (1.4 L) and re-concentrated. The concentrate is diluted with MeOH (14.0 L) and transferred to a reaction vessel. The solution is warmed to about 25° C. then water (14.0 L) is added over about 1-1.5 h; after about 10 L of water is added, the mixture is seeded and a hazy suspension is observed. Additional water (8.4 L) is added over 1.5 h to further precipitate the product. After aging, the solid is collected by filtration. The filter-cake is washed with heptane (5.6 L) and dried to afford tert-butyl 4-((hydroxyimino)methyl)benzyl(tetrahydro-2H-pyran-4-yl)carbamate (A-4) (1678 g; 71% 71% yield, 91.5 area % purity by HPLC) as an off-white powder. 1H NMR (400 MHz, CDCl3) δ 8.12 (s, 1H), 7.51 (d, J=8.2 Hz, 2H), 7.24 (d, J=7.9 Hz, 2H), 4.40 (br s, 3H), 3.96 (dd, J=10.4, 3.6 Hz, 2H), 3.41 (br m, 2H), 1.69-1.61 (m, 4H), 1.39 (br s, 9H).
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