Sodium Chloride → HCID 59656747, compound

tert-butyl 1-(tertbutyldimethylsilyloxy)-3-oxopentan-2-ylcarbamate (26) (900 mg, 2.7 mmol, 1.0 equiv.) was added to a 100 mL RBF followed by a 1:1 mixture of THF/H2O (14 mL). The mixture was stirred and glacial acetic acid (21 mL) was added to the reaction flask. The reaction stirred for 22 h at rt. The reaction was transferred to a 250 mL separatory funnel with sat. NaCl (50 mL) and sat. NaHCO3 (30 mL). The aqueous layer was extracted with EtOAc (3×75 mL) and the combined organic layers were dried over Na2SO4. The solution was then concentrated on a rotary evaporator and dried under vacuum to give 825 mg of crude oil. The residue was purified by flash column chromatography (50% EtOAc/hexanes) to give 570 mg (96%) of 27 as a colorless oil. Rf=0.31 (50% EtOAc/hexanes); IR (film) 3420, 2976, 2937, 1686, 1498, 1365, 1163, 1056 cm−1; 1H NMR (500 MHz, CDCl3) δ 5.78 (d, J=6.0 Hz, 1H, carbamate-NH), 4.34 (br s, 1H, Boc-NH—CH), 3.97 (d, J=10.0 Hz, 1H, CH—CH2), 3.87 (d, J=10.0 Hz, 1H, CH—CH2), 3.34 (br s, 1H, CH2—OH), 2.66 (m, 1H, O═C—CH2), 2.59 (m, 1H, O═CCH2), 1.45 (s, 9H, t-butyl-CH3), 1.09 (t, J=7.0 Hz, 3H, O═C—CH2CH3); 13C NMR (125 MHz, CDCl3) δ 209.0, 156.1, 80.3, 63.1, 61.5, 33.4, 28.4, 7.5.

1. stirringThe reaction stirred for 22 h at rt
2. extractionThe aqueous layer was extracted with EtOAc (3×75 mL)
3. dry with materialthe combined organic layers were dried over Na2SO4
4. concentrationThe solution was then concentrated on a rotary evaporator
5. customdried under vacuum
6. customto give 825 mg of crude oil
7. customThe residue was purified by flash column chromatography (50% EtOAc/hexanes)

ORD record

ord-a951fa9e94a44bf0945afb81c13cf939

Source dataset

uspto-grants-2008_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07329775B2