Imidazole → (2S,3R)-2-tert-Butoxycarbonylamino-3-(tert-butyl-diphenyl-silanyloxy)-butyric acid methyl ester

HRID 2285379ノート

反応式

HRID 2285379 の反応式
[CH3:1][O:2][C:3](=[O:16])[C@@H:4]([NH:8][C:9]([O:11][C:12]([CH3:15])([CH3:14])[CH3:13])=[O:10])[C@H:5]([OH:7])[CH3:6].[C:17]([Si:21](Cl)([C:28]1[CH:33]=[CH:32][CH:31]=[CH:30][CH:29]=1)[C:22]1[CH:27]=[CH:26][CH:25]=[CH:24][CH:23]=1)([CH3:20])([CH3:19])[CH3:18].N1C=CN=C1>CN(C)C=O.O>[CH3:1][O:2][C:3](=[O:16])[C@@H:4]([NH:8][C:9]([O:11][C:12]([CH3:15])([CH3:14])[CH3:13])=[O:10])[C@H:5]([O:7][Si:21]([C:17]([CH3:20])([CH3:19])[CH3:18])([C:28]1[CH:29]=[CH:30][CH:31]=[CH:32][CH:33]=1)[C:22]1[CH:27]=[CH:26][CH:25]=[CH:24][CH:23]=1)[CH3:6]

参加物

6

反応物 3

HCID 795ImidazoleHCID 94078tert-ButyldiphenylchlorosilaneHCID 11368286Methyl N-(tert-butoxycarbonyl)-L-threoninate

生成物 1

HCID 10719205(2S,3R)-2-tert-Butoxycarbonylamino-3-(tert-butyl-diphenyl-silanyloxy)-butyric acid methyl ester収率 95.2%

試薬・触媒・溶媒 2

HCID 962Water溶媒HCID 6228Dimethylformamide溶媒

実験手順

(2S,3R)-2-tert-Butoxycarbonylamino-3-hydroxy-butyric acid methyl ester (1.85 g, 7.93 mmol) was dissolved in N,N-dimethylformamide (10 mL), under an atmosphere of nitrogen. tert-Butyl(chloro)diphenylsilane (2.89 mL, 11.1 mmol) was added followed by imidazole (1.08 g, 15.9 mmol) and the reaction was left to stir for 72 h. The reaction mixture was diluted with water and then extracted with ethyl acetate. The combined organics were dried over anhydrous sodium sulfate, filtered and concentrated. The residue was purified by silica gel chromatography using a stepwise gradient iso-hexanes/ethyl acetate from 1:0 to 4:1 to afford the title compound (3.56 g, 95%) as a pale Greene oil. 1H NMR (300 MHz, CDCl3) δ 0.89 (d, J=6.6 Hz, 3H), 1.04 (s, 9H), 1.10 (s, 9H), 3.64 (s, 3H), 4.18-4.26 (m, 1H), 4.39-4.50 (m, 1H), 5.34 (d, J=9.9 Hz, 1H), 7.36-7.50 (m, 6H), 7.60-7.69 (m, 2H), 7.71-7.77 (m, 2H). LCMS (m/z) 472.2 [M+H], Tr=4.13 min.

後処理

  1. waitthe reaction was left
  2. extractionextracted with ethyl acetate
  3. dry with materialThe combined organics were dried over anhydrous sodium sulfate
  4. filtrationfiltered
  5. concentrationconcentrated
  6. customThe residue was purified by silica gel chromatography

出典と根拠

ORDレコード
ord-f2a849630455456bb9101ab5234addcb
出典データセット
uspto-grants-2015_09
特許番号
US09145441B2

反応ノート

読み込み中…