Hydroxyamine hydrochloride → 4-(2,2,2-Trifluoroethyl-1-oxime)benzyl Alcohol tert-Butyl(dimethyl)silyl Ether

Beteiligte Stoffe

Reaktionsschritte

Hydroxylamine hydrochloride (6.55 g, 94.3 mmol) was added to a pyridine (30 mL) solution of 1-(4-((tert.-butyldimethylsilyloxy)methyl)phenyl)-2,2,2-trifluoroethanone (10 g, 31.4 mmol). The solution was stirred a reflux (4 h). The pyridine was evaporated and 150 mL of an aqueous solution of citric acid (10%) and CH2Cl2 (100 mL) were added to the residue and the organic layer was extracted. The aqueous layer was washed 2 times with CH2Cl2 (2×100 mL). Finally, the organic layers were combined and concentrated in vacuum. The residue was purified by silica gel flash chromatography (MPLC) to obtain 8.4 g of a white solid. Rf=0.31 (1/9 EtOAc/hexanes); mp 63-65° C.; 1H NMR (CDCl3): δ 0.12 (s, (CH3)2Si), 0.96 (s, CH3)3C), 4.73 (s, CH2), 7.44 (d, J=8.2 Hz, C6H4), 7.50 (d, J=8.2 Hz, C6H4), 8.61 (s, OH); 13C NMR (CDCl3): δ −5.3 (CH3Si), 18.4 (C(CH3)3), 25.9 (C(CH3)3), 64.4 (CH2O), 120.6 (q, J=273.2 Hz, CF3), 124.4 (C6H2), 125.9 (C6H2), 128.6 (C6H2), 144.2, (C6H2), 147.9 (q, J=32.1 Hz, CN).

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