Ethanolamine → N-Methyl-N-methoxy2-(S)-hydroxy-3-cyclobutyl Propanamide

HRID 1068107ノート

反応式

HRID 1068107 の反応式
[CH3:1][N:2]([O:12][CH3:13])[C:3](=[O:11])[C:4](=[O:10])[CH2:5][CH:6]1[CH2:9][CH2:8][CH2:7]1.B1([C@H]2[C@H](C)[C@@H]3C(C)(C)[C@H](C3)C2)C2CCCC1CCC2.C(=O)C(C)C.C(CN)O>C1COCC1.CCOCC>[CH3:1][N:2]([O:12][CH3:13])[C:3](=[O:11])[C@@H:4]([OH:10])[CH2:5][CH:6]1[CH2:7][CH2:8][CH2:9]1

参加物

7

実験手順

A mixture of 11.40 g (61.5 mmol) of N-methyl-N-methoxy 2-oxo-3-cyclobutyl propanamide (from Step B) and 250 mL 0.5 N (R)-Alpine Borane® solution in THF was concentrated and stirred at rt for 5 days. The mixture was cooled to 0° C. and quenched with 6.8 mL (75.0 mmol) of isobutyraldehyde. The resulting mixture was diluted with 200 mL of ether and treated with 7.5 mL (125 mmol) of ethanolamine. The precipitate that formed was filtered and the filtrate was concentrated. Flash chromatography on 500 g of silica gel using 9:1 v/v CH2Cl2 as the eluant afforded 11.48 g (99%, 91% ee) of the title compound: 1H NMR (500 MHz) δ 1.59-1.70 (m, 2H), 1.67 (s, 1H), 1.77-1.83 (m, 2H), 1.82-1.92 (m, 1H), 2.03-2.13 (m, 2H), 2.53-2.60 (m, 1H), 3.23 (s, 3H), 3.72 (s, 3H), 4.31 (app d, J=5.5, 1H); HPLC: Chiralpak AS 4.6×250 mm column, 75/25 hexanes/iPrOH, 0.5 mL/min, 210 nm. Retention Times: (S)-Enantiomer, 13.3 min; (R)-enantiomer, 17.2 min.

後処理

  1. concentrationwas concentrated
  2. temperatureThe mixture was cooled to 0° C.
  3. customThe precipitate that formed
  4. filtrationwas filtered
  5. concentrationthe filtrate was concentrated

出典と根拠

ORDレコード
ord-8e6cc611118e443ea900bbd0c40c9d01
出典データセット
uspto-grants-2001_06
特許番号
US06248755B1

反応ノート

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