(R)-Methyl 2-amino-3-phenylpropanoate → (2R)-2-(2-(tert-butoxycarbonylamino)ethylamino)-3-phenylpropionic acid methyl ester

HRID 581192

反応式

HRID 581192 の反応式
[CH3:1][O:2][C:3](=[O:13])[C@H:4]([NH2:12])[CH2:5][C:6]1[CH:11]=[CH:10][CH:9]=[CH:8][CH:7]=1.[C:14]([O:18][C:19](=[O:24])[NH:20][CH2:21][CH:22]=O)([CH3:17])([CH3:16])[CH3:15].C([BH3-])#N.[Na+]>CO.C(O)(=O)C>[CH3:1][O:2][C:3](=[O:13])[C@H:4]([NH:12][CH2:22][CH2:21][NH:20][C:19]([O:18][C:14]([CH3:17])([CH3:16])[CH3:15])=[O:24])[CH2:5][C:6]1[CH:11]=[CH:10][CH:9]=[CH:8][CH:7]=1

参加物

6

反応物 3

HCID 853474(R)-Methyl 2-amino-3-phenylpropanoateHCID 4247255tert-butyl N-(2-oxoethyl)carbamateHCID 5003444Sodium cyanoborohydride

生成物 1

HCID 54571530(2R)-2-(2-(tert-butoxycarbonylamino)ethylamino)-3-phenylpropionic acid methyl ester収率 42.8%

試薬・触媒・溶媒 2

HCID 176Acetic Acid溶媒HCID 887Methanol溶媒

反応条件

温度
0 °C

実験手順

(2R)-2-Amino-3-phenylpropionic acid methyl ester (3.2 g; 15.0 mmol) and (2-oxoethyl)carbamic acid tert-butyl ester (3.2 g; 20.0 mmol) (prepared as in Dueholm et al, Org. Prep. Proced. Int. 25(4), 457-61 (1993)) were dissolved in a mixture of methanol (100 ml) and acetic acid (5 ml). Molecular sieves (3 Å; 100 g) were added and the reaction mixture was cooled to 0° C. Sodium cyanoborohydride (1.38 g; 22.0 mmol) was added portionwise and the reaction mixture was left without stirring for 12 h. The reaction mixture was filtered and water (100 ml), aqueous sodium hydrogencarbonate/sodium carbonate (10%; 100 ml; pH 9) and methylene chloride (50 ml) were added to the filtrate. The aqueous phase was extracted with methylene chloride (2×50 ml) and the combined organic phases were dried over magnesium sulfate. The organic phase was evaporated in vacuo and the residue was chromatographed on silica (4×40 cm) using ethyl acetate/heptane (3:2) as eluent to afford 2.07 g of (2R)-2-(2-(tert-butoxycarbonylamino)ethylamino)-3-phenylpropionic acid methyl ester.

後処理

  1. additionMolecular sieves (3 Å; 100 g) were added
  2. waitthe reaction mixture was left
  3. filtrationThe reaction mixture was filtered
  4. additionwater (100 ml), aqueous sodium hydrogencarbonate/sodium carbonate (10%; 100 ml; pH 9) and methylene chloride (50 ml) were added to the filtrate
  5. extractionThe aqueous phase was extracted with methylene chloride (2×50 ml)
  6. dry with materialthe combined organic phases were dried over magnesium sulfate
  7. customThe organic phase was evaporated in vacuo
  8. customthe residue was chromatographed on silica (4×40 cm)

出典と根拠

ORDレコード
ord-5d8278e5d57b43e3990ad189c9e57d93
出典データセット
uspto-grants-1999_07
特許番号
US05919777

関連ノート

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