(S)-Tert-butyl 2,2-dimethyl-4-(2-oxoethyl)oxazolidine-3-carboxylate → 2,2-Dimethyloxazolidine-3-carboxylic acid tert-butyl ester

HRID 2276369노트

반응식

HRID 2276369 반응식
[C:1]([O:5][C:6]([N:8]1[C@@H:12](CC=O)[CH2:11][O:10][C:9]1([CH3:17])[CH3:16])=[O:7])([CH3:4])([CH3:3])[CH3:2].C([Mg]Br)C>C(OCC)C>[C:1]([O:5][C:6]([N:8]1[CH2:12][CH2:11][O:10][C:9]1([CH3:17])[CH3:16])=[O:7])([CH3:4])([CH3:2])[CH3:3]

참가 물질

4

반응물 2

HCID 10586317(S)-Tert-butyl 2,2-dimethyl-4-(2-oxoethyl)oxazolidine-3-carboxylateHCID 178418443HCID 178418443, 화합물

생성물 1

HCID 545314052,2-Dimethyloxazolidine-3-carboxylic acid tert-butyl ester수율 56.9%

시약·촉매·용매 1

HCID 3283Diethyl Ether용매2회

실험 절차

To a stirred solution of (S)-2,2-dimethyl-4-(2-oxo-ethyl)-oxazolidine-3-carboxylic acid tert-butyl ester (15.5 g; CAS 147959-19-1) in dry diethyl ether (100 ml) under an argon atmosphere at room temperature was added dropwise a solution of ethylmagnesium bromide in diethyl ether (42.6 ml, 3 M solution) and stirring continued for 1 hour. The reaction mixture was then quenched by careful addition of water (10 ml) and the mixture was then filtered through decalite. The filtrate was washed sequentially with water and with saturated brine and then the organic phase was separated, dried over sodium sulphate, filtered and concentrated in vacuo. The reside was purified by column chromatography (SiO2; gradient: heptane/EtOAc 100:0→50:50) to give (S)-4-(R)-2-hydroxy-butyl)-2,2-dimethyl-oxazolidine-3-carboxylic acid tert-butyl ester (7.30 g) from fractions eluting first and (S)-4-(S)-2-hydroxy-butyl)-2,2-dimethyl-oxazolidine-3-carboxylic acid tert-butyl ester (6.44 g) from fractions eluting later, both compounds as colourless oils. (S)-4-(R)-2-Hydroxy-butyl)-2,2-dimethyl-oxazolidine-3-carboxylic acid tert-butyl ester: 1H NMR δ (CDCl3, 300 MHz): 4.52 (1H, br. D, J=3.3 Hz), 4.23 (1H, m), 4.00 (1H, dd, J=8.7 & 5.4 Hz), 3.66 (1H, d, J=8.7 Hz), 3.40 (1H, m), 1.79 (1H, td, J=11.4 & 2.1 Hz), 1.60-1.44 (16H, m), 0.95 (3H, t, J=7.5 Hz). (S)-4-((S)-2-Hydroxy-butyl)-2,2-dimethyl-oxazolidine-3-carboxylic acid tert-butyl ester: 1H NMR δ (CDCl3, 300 MHz): 4.12 (1H, m), 3.98 (1H, dd, J=9.0 & 5.7 Hz), 3.82 (1H, m), 3.55 (1H, m), 2.88 (1H, br. s), 1.79 (1H, m), 1.70-1.40 (16H, m), 0.95 (3H, t, J=7.5 Hz).

후처리

  1. customThe reaction mixture was then quenched by careful addition of water (10 ml)
  2. filtrationthe mixture was then filtered through decalite
  3. washThe filtrate was washed sequentially with water and with saturated brine
  4. customthe organic phase was separated
  5. dry with materialdried over sodium sulphate
  6. filtrationfiltered
  7. concentrationconcentrated in vacuo
  8. customThe reside was purified by column chromatography (SiO2; gradient: heptane/EtOAc 100:0→50:50)

출처 및 근거

ORD 기록
ord-2595bf888afa47d1b403b2c5b5ffd24e
출처 데이터셋
uspto-grants-2015_09
특허 번호
US09132136B2

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