Methanol → Methyl 2-(5-bromopyridin-2-yl)acetate
反応式
[Br:1][C:2]1[CH:3]=[CH:4][C:5]([CH2:8][C:9]([OH:11])=[O:10])=[N:6][CH:7]=1.S(Cl)(Cl)=O.[CH3:16]O>>[CH3:16][O:10][C:9](=[O:11])[CH2:8][C:5]1[CH:4]=[CH:3][C:2]([Br:1])=[CH:7][N:6]=1参加物
実験手順
Key building block 2-(5-bromo-pyridin-2-yl)-5-chloro-pentanoic acid (XII) can be prepared according to Scheme 8. Starting with commercially available 5-bromo-2-iodo-pyridine (XXXV), copper-catalyzed reaction with malonic acid diethyl ester furnishes 2-(5-bromo-pyridin-2-yl)-malonic acid diethyl ester (XXXVI). Hydrolysis and decarboxylation under basic conditions gives (5-bromo-pyridin-2-yl)-acetic acid (XXXVII), which subsequently can undergo nucleophilic acyl substitution with thionyl chloride in methanol to provide (5-bromo-pyridin-2-yl)-acetic acid methyl ester (XXXVIII). Deprotonation of XXXVIII with strong base followed by alkylation with 1-bromo-3-chloropropane gives 2-(5-bromo-pyridin-2-yl)-5-chloro-pentanoic acid methyl ester (XXXIX), which can then be hydrolyzed under aqueous basic conditions to furnish key building block 2-(5-bromo-pyridin-2-yl)-5-chloro-pentanoic acid (XII).
後処理
- customHydrolysis and decarboxylation under basic conditions
出典と根拠
- ORDレコード
- ord-44ba62b900434a189319d8b637d8c795
- 出典データセット
- uspto-grants-2012_06
- 特許番号
- US08202866B2
反応ノート
読み込み中…