Реакция #48542

ord-50d8dfd3760f45d5ae82826e18b0a2f3

Растворители

Условия реакции

Температура
-78°CELSIUS
Подробные условия
See reaction.notes.procedure_details.

Обработка

  1. 1
    Температураthe reaction mixture was warmed to 0° C.
  2. 2
    Другоеquenched with saturated aqueous NH4Cl (200 mL)
  3. 3
    ДругоеThe quenched reaction mixture
  4. 4
    Промывкаwashed with water (3×200 mL) and brine (200 mL)
  5. 5
    Сушкаdried (Na2SO4)
  6. 6
    Фильтрацияfiltered

Методика

To a solution of (2R,4S)-2-tert-butyl-3-formyloxazolidine-4-carboxylic acid methyl ester (4.6 g, 21.4 mmol) [see D. Seebach, J. D. Aebi, M. Gander-Coquoz and R. Naef, Helv. Chim. Acta., 70, 1194 (1987)] in dry THF (120 mL) under N2 was added 1-iodobutane (12.2 mL, 106.8 mmol) and HMPA (12 mL). The mixture was cooled to −78° C. and a solution of sodium bis(trimethylsilyl)amide in THF (1 M, 32 mL, 32 mmol) was added dropwise over 15 minutes. After 2 h, the reaction mixture was warmed to 0° C. and quenched with saturated aqueous NH4Cl (200 mL). The quenched reaction mixture was diluted with ether (400 mL) and washed with water (3×200 mL) and brine (200 mL), then dried (Na2SO4) and filtered. Concentration of the filtrate and flash chromatography of the residue (20% ethyl acetate/hexanes) provided the title compound as a pale brown solid (4.0 g, 69%). MS(ES) m/e 272 [M+H]+.

Источник

DOI: 10.6084/m9.figshare.5104873.v1Патент: US07745637B2uspto-grants-2010_06