Hydroxyamine hydrochloride → ((R)-1-benzyloxymethyl-3-butenyloxy)acetaldehyde oxime

Temperature

60 °C

{[(2R)-1-(Benzyloxy)pent-4-en-2-yl]oxy}acetaldehyde (C3) (7.76 g, ≦32.88 mmol) was dissolved in a 2:1 mixture of ethanol and water (127 mL). Sodium acetate (13.6 g, 166 mmol) was added, and the mixture was stirred for 15 minutes. Hydroxylamine hydrochloride (98%, 7.05 g, 99.4 mmol) was then added, and the reaction mixture was heated to 60° C. for 18 hours. The reaction mixture was partitioned between ethyl acetate and water; the aqueous layer was extracted with ethyl acetate, and the combined organic layers were washed with saturated aqueous sodium chloride solution, dried over sodium sulfate, filtered, and concentrated in vacuo. Silica gel chromatography (Gradient: 0% to 30% ethyl acetate in heptane) afforded the product as a colorless oil, presumed from the 1H NMR spectrum to be a mixture of E and Z oximes. Yield: 7.12 g, 28.6 mmol, 87% over two steps. 1H NMR (400 MHz, CDCl3) δ 2.30-2.37 (m, 2H), 3.47-3.65 (m, 3H), {[4.20 (dd, half of ABX pattern, J=12.9, 5.8 Hz) and 4.25 (dd, half of ABX pattern, J=12.9, 5.6 Hz)] and 4.45-4.49 (br m), total 2H}, 4.55 and 4.56 (2 s, total 2H), 5.05-5.14 (m, 2H), 5.75-5.87 (m, 1H), 6.93-7.01 and 7.47-7.55 (2 br m, total 1H), 7.27-7.39 (m, 5H).

1. customThe reaction mixture was partitioned between ethyl acetate and water
2. extractionthe aqueous layer was extracted with ethyl acetate
3. washthe combined organic layers were washed with saturated aqueous sodium chloride solution
4. dry with materialdried over sodium sulfate
5. filtrationfiltered
6. concentrationconcentrated in vacuo

ORD record

ord-ab1b6d44b3df45d9bcbee1f5f332349b

Source dataset

uspto-grants-2015_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08933221B2